diff --git a/chart/openfaas/README.md b/chart/openfaas/README.md
index aa0f26dff..5dc9973bd 100644
--- a/chart/openfaas/README.md
+++ b/chart/openfaas/README.md
@@ -651,4 +651,6 @@ For legacy scaling in OpenFaaS Community Edition.
 | ----------------------- | ----------------------------------    | ---------------------------------------------------------- |
 | `prometheus.create` | Create the Prometheus component | `true` |
 | `prometheus.image` | Container image used for prometheus | See [values.yaml](./values.yaml) |
+| `prometheus.retention.time` | When to remove old data from the prometheus db. | `15d` |
+| `prometheus.retention.size` | The maximum number of bytes of storage blocks to retain. Units supported: B, KB, MB, GB, TB, PB, EB. 0 meaning disabled. See: [Prometheus storage](https://prometheus.io/docs/prometheus/latest/storage/#operational-aspects)| `0` |
 | `prometheus.resources` | Resource limits and requests for prometheus containers | See [values.yaml](./values.yaml) |
diff --git a/chart/openfaas/templates/prometheus-dep.yaml b/chart/openfaas/templates/prometheus-dep.yaml
index 32521434c..a227ee431 100644
--- a/chart/openfaas/templates/prometheus-dep.yaml
+++ b/chart/openfaas/templates/prometheus-dep.yaml
@@ -37,6 +37,12 @@ spec:
         command:
           - "prometheus"
           - "--config.file=/etc/prometheus/prometheus.yml"
+          {{- if .Values.prometheus.retention.time }}
+          - "--storage.tsdb.retention.time={{.Values.prometheus.retention.time}}"
+          {{- end }}
+          {{-  if .Values.prometheus.retention.size }}
+          - "--storage.tsdb.retention.size={{.Values.prometheus.retention.size}}"
+          {{- end }}
         imagePullPolicy: {{ .Values.openfaasImagePullPolicy }}
         livenessProbe:
           {{- if .Values.httpProbe }}
diff --git a/chart/openfaas/values.yaml b/chart/openfaas/values.yaml
index dce5efe1b..d7537e7f0 100644
--- a/chart/openfaas/values.yaml
+++ b/chart/openfaas/values.yaml
@@ -331,6 +331,8 @@ iam:
 prometheus:
   image: prom/prometheus:v2.51.2
   create: true
+  retention:
+    time: 15d
   resources:
     requests:
       memory: "512Mi"