diff --git a/docs/DeveloperGuide.md b/docs/DeveloperGuide.md
index c734cb2d8e0..742529d9457 100644
--- a/docs/DeveloperGuide.md
+++ b/docs/DeveloperGuide.md
@@ -143,12 +143,15 @@ The `Model` component,
 
 **API** : [`Storage.java`](https://github.com/se-edu/addressbook-level3/tree/master/src/main/java/seedu/address/storage/Storage.java)
 
-<puml src="diagrams/StorageClassDiagram.puml" width="550" />
+<puml src="diagrams/StorageClassDiagram.puml" width="850" />
 
 The `Storage` component,
-* can save both address book data and user preference data in JSON format, and read them back into corresponding objects.
-* inherits from both `AddressBookStorage` and `UserPrefStorage`, which means it can be treated as either one (if only the functionality of only one is needed).
-* depends on some classes in the `Model` component (because the `Storage` component's job is to save/retrieve objects that belong to the `Model`)
+* can save address book data, task list data and user preference data in JSON format, and read 
+them back into corresponding objects.
+* inherits from AddressBookStorage, TaskListStorage and UserPrefStorage, which means it can be 
+treated as one of the three classes (if only the functionality of only one is needed).
+* depends on some classes in the `Model` component (because the `Storage` component's job is to 
+save/retrieve objects that belong to the `Model`)
 
 ### Common classes
 
diff --git a/docs/diagrams/StorageClassDiagram.puml b/docs/diagrams/StorageClassDiagram.puml
index a821e06458c..c6b84178d96 100644
--- a/docs/diagrams/StorageClassDiagram.puml
+++ b/docs/diagrams/StorageClassDiagram.puml
@@ -22,6 +22,13 @@ Class JsonAdaptedPerson
 Class JsonAdaptedTag
 }
 
+package "TaskList Storage" #F4F6F6{
+Class "<<interface>>\nTaskListStorage" as TaskListStorage
+Class JsonTaskListStorage
+Class JsonSerializableTaskList
+Class JsonAdaptedTask
+}
+
 }
 
 Class HiddenOutside #FFFFFF
@@ -30,9 +37,13 @@ HiddenOutside ..> Storage
 StorageManager .up.|> Storage
 StorageManager -up-> "1" UserPrefsStorage
 StorageManager -up-> "1" AddressBookStorage
+StorageManager -up-> "1" TaskListStorage
+
 
 Storage -left-|> UserPrefsStorage
 Storage -right-|> AddressBookStorage
+Storage -down-|> TaskListStorage
+
 
 JsonUserPrefsStorage .up.|> UserPrefsStorage
 JsonAddressBookStorage .up.|> AddressBookStorage
@@ -40,4 +51,11 @@ JsonAddressBookStorage ..> JsonSerializableAddressBook
 JsonSerializableAddressBook --> "*" JsonAdaptedPerson
 JsonAdaptedPerson --> "*" JsonAdaptedTag
 
+JsonTaskListStorage .up.|> TaskListStorage
+JsonTaskListStorage ..> JsonSerializableTaskList
+JsonSerializableTaskList --> "*" JsonAdaptedTask
+
+Storage .[hidden]down. StorageManager
+StorageManager .[hidden]down. UserPrefsStorage
+
 @enduml