diff --git a/charts/kube-prometheus-stack/Chart.yaml b/charts/kube-prometheus-stack/Chart.yaml
index e384050e7546..1186e5e7175c 100644
--- a/charts/kube-prometheus-stack/Chart.yaml
+++ b/charts/kube-prometheus-stack/Chart.yaml
@@ -21,7 +21,7 @@ name: kube-prometheus-stack
 sources:
   - https://github.com/prometheus-community/helm-charts
   - https://github.com/prometheus-operator/kube-prometheus
-version: 51.3.0
+version: 51.3.1
 appVersion: v0.68.0
 kubeVersion: ">=1.19.0-0"
 home: https://github.com/prometheus-operator/kube-prometheus
diff --git a/charts/kube-prometheus-stack/templates/thanos-ruler/ruler.yaml b/charts/kube-prometheus-stack/templates/thanos-ruler/ruler.yaml
index 505d68b025d8..6d8c12a93aa6 100644
--- a/charts/kube-prometheus-stack/templates/thanos-ruler/ruler.yaml
+++ b/charts/kube-prometheus-stack/templates/thanos-ruler/ruler.yaml
@@ -73,7 +73,8 @@ spec:
 {{- end }}
 {{- if .Values.thanosRuler.thanosRulerSpec.alertmanagersConfig }}
   alertmanagersConfig:
-{{ toYaml .Values.thanosRuler.thanosRulerSpec.alertmanagersConfig | indent 4 }}
+    key: alertmanager-configs.yaml
+    name: {{ template "kube-prometheus-stack.thanosRuler.name" . }}
 {{- end }}
 {{- if .Values.thanosRuler.thanosRulerSpec.queryEndpoints }}
   queryEndpoints:
diff --git a/charts/kube-prometheus-stack/templates/thanos-ruler/secret.yaml b/charts/kube-prometheus-stack/templates/thanos-ruler/secret.yaml
new file mode 100644
index 000000000000..ede29be714cd
--- /dev/null
+++ b/charts/kube-prometheus-stack/templates/thanos-ruler/secret.yaml
@@ -0,0 +1,14 @@
+{{- if .Values.thanosRuler.enabled }}
+apiVersion: v1
+kind: Secret
+metadata:
+  name: {{ template "kube-prometheus-stack.thanosRuler.name" . }}
+  namespace: {{ template "kube-prometheus-stack.namespace" . }}
+  labels:
+    app: {{ include "kube-prometheus-stack.thanosRuler.name" . }}
+{{ include "kube-prometheus-stack.labels" . | indent 4 }}
+data:
+{{- if .Values.thanosRuler.thanosRulerSpec.alertmanagersConfig }}
+  alertmanager-configs.yaml: {{ toYaml .Values.thanosRuler.thanosRulerSpec.alertmanagersConfig | b64enc | quote }}
+{{- end }}
+{{- end }}