diff --git a/examples/alerts/alerts.md b/examples/alerts/alerts.md
index d603e751b2..dad259a3d0 100644
--- a/examples/alerts/alerts.md
+++ b/examples/alerts/alerts.md
@@ -142,6 +142,34 @@ rules:
   for: 5m
   labels:
     severity: warning
+- alert: ThanosRulerQueryHighDNSFailures
+  annotations:
+    message: Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing
+      DNS queries for query endpoints.
+  expr: |
+    (
+      sum by (job) (rate(thanos_ruler_query_apis_dns_failures_total{job=~"thanos-ruler.*"}[5m]))
+    /
+      sum by (job) (rate(thanos_ruler_query_apis_dns_lookups_total{job=~"thanos-ruler.*"}[5m]))
+    * 100 > 1
+    )
+  for: 15m
+  labels:
+    severity: warning
+- alert: ThanosRulerAlertmanagerHighDNSFailures
+  annotations:
+    message: Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing
+      DNS queries for Alertmanager endpoints.
+  expr: |
+    (
+      sum by (job) (rate(thanos_ruler_alertmanagers_dns_failures_total{job=~"thanos-ruler.*"}[5m]))
+    /
+      sum by (job) (rate(thanos_ruler_alertmanagers_dns_lookups_total{job=~"thanos-ruler.*"}[5m]))
+    * 100 > 1
+    )
+  for: 15m
+  labels:
+    severity: warning
 ```
 
 ## Store Gateway
diff --git a/examples/alerts/alerts.yaml b/examples/alerts/alerts.yaml
index 434d741d58..5011e882b4 100644
--- a/examples/alerts/alerts.yaml
+++ b/examples/alerts/alerts.yaml
@@ -354,6 +354,34 @@ groups:
     for: 5m
     labels:
       severity: warning
+  - alert: ThanosRulerQueryHighDNSFailures
+    annotations:
+      message: Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing
+        DNS queries for query endpoints.
+    expr: |
+      (
+        sum by (job) (rate(thanos_ruler_query_apis_dns_failures_total{job=~"thanos-ruler.*"}[5m]))
+      /
+        sum by (job) (rate(thanos_ruler_query_apis_dns_lookups_total{job=~"thanos-ruler.*"}[5m]))
+      * 100 > 1
+      )
+    for: 15m
+    labels:
+      severity: warning
+  - alert: ThanosRulerAlertmanagerHighDNSFailures
+    annotations:
+      message: Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing
+        DNS queries for Alertmanager endpoints.
+    expr: |
+      (
+        sum by (job) (rate(thanos_ruler_alertmanagers_dns_failures_total{job=~"thanos-ruler.*"}[5m]))
+      /
+        sum by (job) (rate(thanos_ruler_alertmanagers_dns_lookups_total{job=~"thanos-ruler.*"}[5m]))
+      * 100 > 1
+      )
+    for: 15m
+    labels:
+      severity: warning
 - name: thanos-component-absent.rules
   rules:
   - alert: ThanosCompactorIsDown
diff --git a/mixin/thanos/alerts/ruler.libsonnet b/mixin/thanos/alerts/ruler.libsonnet
index 16d5c4e486..83f4d59807 100644
--- a/mixin/thanos/alerts/ruler.libsonnet
+++ b/mixin/thanos/alerts/ruler.libsonnet
@@ -114,6 +114,42 @@
               severity: 'warning',
             },
           },
+          {
+            alert: 'ThanosRulerQueryHighDNSFailures',
+            annotations: {
+              message: 'Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing DNS queries for query endpoints.',
+            },
+            expr: |||
+              (
+                sum by (job) (rate(thanos_ruler_query_apis_dns_failures_total{%(selector)s}[5m]))
+              /
+                sum by (job) (rate(thanos_ruler_query_apis_dns_lookups_total{%(selector)s}[5m]))
+              * 100 > 1
+              )
+            ||| % thanos.ruler,
+            'for': '15m',
+            labels: {
+              severity: 'warning',
+            },
+          },
+          {
+            alert: 'ThanosRulerAlertmanagerHighDNSFailures',
+            annotations: {
+              message: 'Thanos Ruler {{$labels.job}} have {{ $value | humanize }}% of failing DNS queries for Alertmanager endpoints.',
+            },
+            expr: |||
+              (
+                sum by (job) (rate(thanos_ruler_alertmanagers_dns_failures_total{%(selector)s}[5m]))
+              /
+                sum by (job) (rate(thanos_ruler_alertmanagers_dns_lookups_total{%(selector)s}[5m]))
+              * 100 > 1
+              )
+            ||| % thanos.ruler,
+            'for': '15m',
+            labels: {
+              severity: 'warning',
+            },
+          },
         ],
       },
     ],