diff --git a/CHANGES.md b/CHANGES.md
index e438ca6..9e5fb7c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -135,6 +135,8 @@ To be released.
     );
     ~~~~~~~~
 
+ -  Deprecated `uri` and `url` type is added.  [[#126], [#277]]
+
 ### Docs target
 
  -  A new required configuration `targets.docs.title` was added.
@@ -253,6 +255,7 @@ To be released.
 
 [#13]: https://github.com/spoqa/nirum/issues/13
 [#100]: https://github.com/spoqa/nirum/issues/100
+[#126]: https://github.com/spoqa/nirum/issues/126
 [#178]: https://github.com/spoqa/nirum/issues/178
 [#217]: https://github.com/spoqa/nirum/issues/217
 [#220]: https://github.com/spoqa/nirum/issues/220
@@ -266,6 +269,7 @@ To be released.
 [#267]: https://github.com/spoqa/nirum/pull/267
 [#269]: https://github.com/spoqa/nirum/pull/269
 [#272]: https://github.com/spoqa/nirum/pull/272
+[#277]: https://github.com/spoqa/nirum/pull/277
 [entry points]: https://setuptools.readthedocs.io/en/latest/pkg_resources.html#entry-points
 [python2-numbers-integral]: https://docs.python.org/2/library/numbers.html#numbers.Integral
 [python2-int]: https://docs.python.org/2/library/functions.html#int
diff --git a/docs/serialization.md b/docs/serialization.md
index c72ead6..f872380 100644
--- a/docs/serialization.md
+++ b/docs/serialization.md
@@ -184,7 +184,7 @@ a structure consists of fields which have their name and type.  For example:
         name name,
         date? dob,
         gender? gender,
-        uri? website-uri
+        url? website-url
     );
 
 It's represented in JSON to:
@@ -198,7 +198,7 @@ It's represented in JSON to:
         },
         "dob": null,
         "gender": "male",
-        "uri": null
+        "url": null
     }
 
 When a payload is deserialized, undefined fields are just ignored.
@@ -229,7 +229,7 @@ a union type instead of a record type:
         name name,
         date? dob,
         gender? gender,
-        uri? website-uri
+        url? website-url
     );
 
 It's represented in JSON to:
@@ -244,7 +244,7 @@ It's represented in JSON to:
         },
         "dob": null,
         "gender": "male",
-        "uri": null
+        "url": null
     }
 
 In a similar way to a recrod type, undefined fields in a payload are ignored
diff --git a/examples/builtins.nrm b/examples/builtins.nrm
index b222d63..f7f4c69 100644
--- a/examples/builtins.nrm
+++ b/examples/builtins.nrm
@@ -53,8 +53,8 @@ record et-cetera (
     uuid b,
     # `uuid` stores a UUID.  Represented as a string in JSON.
 
-    uri c,
-    # `uri` stores a URI.  Represented as a string in JSON.
+    url c,
+    # `url` stores a URL.  Represented as a string in JSON.
 );
 
 record containers (
diff --git a/examples/pdf-service.nrm b/examples/pdf-service.nrm
index cad8444..5c29941 100644
--- a/examples/pdf-service.nrm
+++ b/examples/pdf-service.nrm
@@ -5,12 +5,12 @@ union markdown-parse-error = symbol-error | syntax-error (text reason);
 type html = text;
 
 service pdf-service (
-    # A microservice which renders a PDF from the given URI or HTML.
+    # A microservice which renders a PDF from the given URL or HTML.
 
-    @http-resource(method="GET", path="/pdf/{uri}")
-    binary render-uri (
-        # Renders a PDF from the given URI.
-        uri uri,
+    @http-resource(method="GET", path="/pdf/{url}")
+    binary render-url (
+        # Renders a PDF from the given URL.
+        url url,
     ),
 
     @http-resource(method="POST", path="/pdf/")
diff --git a/src/Nirum/Constructs/Module.hs b/src/Nirum/Constructs/Module.hs
index b228a66..c23c57d 100644
--- a/src/Nirum/Constructs/Module.hs
+++ b/src/Nirum/Constructs/Module.hs
@@ -30,7 +30,7 @@ import Nirum.Constructs.TypeDeclaration ( JsonType (Boolean, Number, String)
                                                                   , Int32
                                                                   , Int64
                                                                   , Text
-                                                                  , Uri
+                                                                  , Url
                                                                   , Uuid
                                                                   )
                                         , Type (PrimitiveType)
@@ -112,7 +112,9 @@ coreTypes =
     -- et cetera
     , decl' "bool" Bool Boolean
     , decl' "uuid" Uuid String
-    , decl' "uri" Uri String
+    , decl' "url" Url String
+    -- FIXME: deprecated
+    , decl' "uri" Url String
     ]
   where
     decl' name prim json =
diff --git a/src/Nirum/Constructs/TypeDeclaration.hs b/src/Nirum/Constructs/TypeDeclaration.hs
index 493da98..92be117 100644
--- a/src/Nirum/Constructs/TypeDeclaration.hs
+++ b/src/Nirum/Constructs/TypeDeclaration.hs
@@ -19,7 +19,7 @@ module Nirum.Constructs.TypeDeclaration ( EnumMember (EnumMember)
                                                                   , Int32
                                                                   , Int64
                                                                   , Text
-                                                                  , Uri
+                                                                  , Url
                                                                   , Uuid
                                                                   )
                                         , Tag ( Tag
@@ -174,7 +174,7 @@ instance Declaration Tag where
 -- | Primitive type identifiers.
 data PrimitiveTypeIdentifier
     = Bigint | Decimal | Int32 | Int64 | Float32 | Float64 | Text | Binary
-    | Date | Datetime | Bool | Uuid | Uri
+    | Date | Datetime | Bool | Uuid | Url
     deriving (Eq, Ord, Show)
 
 -- | Possible coded types of 'PrimitiveType' in JSON representation.
diff --git a/src/Nirum/Targets/Python/Deserializers.hs b/src/Nirum/Targets/Python/Deserializers.hs
index 4eb1603..21aad8c 100644
--- a/src/Nirum/Targets/Python/Deserializers.hs
+++ b/src/Nirum/Targets/Python/Deserializers.hs
@@ -578,7 +578,7 @@ except #{builtins}.ValueError:
     )
         |]
 
-compilePrimitiveTypeDeserializer Uri vInput vOutput vError =
+compilePrimitiveTypeDeserializer Url vInput vOutput vError =
     compilePrimitiveTypeDeserializer Text vInput vOutput vError
 
 -- | Wrap a Python deserializer code block into an isolated scope.
diff --git a/src/Nirum/Targets/Python/Serializers.hs b/src/Nirum/Targets/Python/Serializers.hs
index 1cf1634..2d57161 100644
--- a/src/Nirum/Targets/Python/Serializers.hs
+++ b/src/Nirum/Targets/Python/Serializers.hs
@@ -80,4 +80,4 @@ compilePrimitiveTypeSerializer Datetime var = replace "$var" var [q|(
 )|]
 compilePrimitiveTypeSerializer Bool var = var
 compilePrimitiveTypeSerializer Uuid var = [qq|str($var).lower()|]
-compilePrimitiveTypeSerializer Uri var = var
+compilePrimitiveTypeSerializer Url var = var
diff --git a/src/Nirum/Targets/Python/TypeExpression.hs b/src/Nirum/Targets/Python/TypeExpression.hs
index 8f540fe..63ae522 100644
--- a/src/Nirum/Targets/Python/TypeExpression.hs
+++ b/src/Nirum/Targets/Python/TypeExpression.hs
@@ -82,8 +82,8 @@ compilePrimitiveType primitiveTypeIdentifier' = do
         (Uuid, _) -> do
             uuid <- importStandardLibrary "uuid"
             return [qq|$uuid.UUID|]
-        (Uri, Python2) -> builtins "basestring"
-        (Uri, Python3) -> builtins "str"
+        (Url, Python2) -> builtins "basestring"
+        (Url, Python3) -> builtins "str"
   where
     builtins :: Code -> CodeGen Code
     builtins typename' = do
diff --git a/src/Nirum/Targets/Python/Validators.hs b/src/Nirum/Targets/Python/Validators.hs
index 5dcf461..3c93357 100644
--- a/src/Nirum/Targets/Python/Validators.hs
+++ b/src/Nirum/Targets/Python/Validators.hs
@@ -99,9 +99,9 @@ compilePrimitiveTypeValidator primitiveTypeId pythonVar = do
         [ ValueValidator [qq|(($var).tzinfo is not None)|]
                          "naive datetime (lacking tzinfo)"
         ]
-    vv Uri var =
+    vv Url var =
         [ ValueValidator [qq|('\\n' not in ($var))|]
-                         "URI cannot contain new line characters"
+                         "URL cannot contain new line characters"
         ]
     vv _ _ = []
 
diff --git a/test/Nirum/Targets/Python/TypeExpressionSpec.hs b/test/Nirum/Targets/Python/TypeExpressionSpec.hs
index 87f5f57..8f1de5b 100644
--- a/test/Nirum/Targets/Python/TypeExpressionSpec.hs
+++ b/test/Nirum/Targets/Python/TypeExpressionSpec.hs
@@ -57,7 +57,7 @@ spec = pythonVersionSpecs $ \ ver -> do
         let (uuidCode, uuidContext) = run' (compilePrimitiveType Uuid)
         uuidCode `shouldBe` Right "_uuid.UUID"
         standardImports uuidContext `shouldBe` [("_uuid", "uuid")]
-        code (compilePrimitiveType Uri) `shouldBe`
+        code (compilePrimitiveType Url) `shouldBe`
             case ver of
                 Python2 -> "__builtin__.basestring"
                 Python3 -> "__builtin__.str"
diff --git a/test/nirum_fixture/fixture/foo.nrm b/test/nirum_fixture/fixture/foo.nrm
index e1aa071..e6a2f18 100644
--- a/test/nirum_fixture/fixture/foo.nrm
+++ b/test/nirum_fixture/fixture/foo.nrm
@@ -115,7 +115,7 @@ record product (
     text name,
     int64? price,
     bool sale,
-    uri? url,
+    url? url,
 );
 
 union animal = cat
@@ -142,3 +142,5 @@ record name-shadowing-field-record (
 union optional-union = foo ( int32? bar )
                      | baz ( int32 qux )
                      ;
+
+unboxed website (uri);
diff --git a/test/nirum_fixture/fixture/types.nrm b/test/nirum_fixture/fixture/types.nrm
index 9d89b1b..6bb1205 100644
--- a/test/nirum_fixture/fixture/types.nrm
+++ b/test/nirum_fixture/fixture/types.nrm
@@ -41,7 +41,7 @@ unboxed record-unboxed (product);
 
 union post
     = image (text mime-type, binary data)
-    | link (uri link, text title, text? quote)
+    | link (url link, text title, text? quote)
     | article (text title, text content)
     ;
 
diff --git a/test/python/primitive_test.py b/test/python/primitive_test.py
index 1057010..a1bb2f2 100644
--- a/test/python/primitive_test.py
+++ b/test/python/primitive_test.py
@@ -15,7 +15,7 @@
                          Point1, Point2, Point3d, Pop, PingService, Product,
                          RecordWithMap, RecordWithOptionalRecordField,
                          Rnb, RpcError, Run, Song, Status, Stop, Way,
-                         WesternName)
+                         Website, WesternName)
 from fixture.foo.bar import PathUnbox, IntUnbox, Point
 from fixture.qux import Path, Name
 from fixture.reserved_keyword_enum import ReservedKeywordEnum
@@ -538,3 +538,15 @@ def test_name_shadowing_field():
     assert "bytes must be a value of {0}, not ['invalid']".format(
         'bytes' if PY3 else 'str'
     ) == str(ei.value)
+
+
+def test_uri():
+    """ Deprecated
+    """
+    assert isinstance(Website, type)
+    website = Website(u'https://nirum.org')
+    assert website.value == u'https://nirum.org'
+    assert website.__nirum_serialize__() == u'https://nirum.org'
+    assert Website.__nirum_deserialize__(u'https://nirum.org') == website
+    with raises(ValueError):
+        Website(u'https://nirum.org\n')