diff --git a/base/cert-manager/resources/le-prod-issuer.yaml b/base/cert-manager/resources/le-prod-issuer.yaml
deleted file mode 100644
index ef29048..0000000
--- a/base/cert-manager/resources/le-prod-issuer.yaml
+++ /dev/null
@@ -1,18 +0,0 @@
-apiVersion: cert-manager.io/v1
-kind: ClusterIssuer
-metadata:
-  name: letsencrypt-prod
-spec:
-  acme:
-    # The ACME server URL
-    server: https://acme-v02.api.letsencrypt.org/directory
-    # Email address used for ACME registration
-    email: adminfra@cadoles.com
-    # Name of a secret used to store the ACME account private key
-    privateKeySecretRef:
-      name: letsencrypt-prod
-    # Enable the HTTP-01 challenge provider
-    solvers:
-    - http01:
-        ingress:
-          ingressClassName: nginx
diff --git a/base/cert-manager/resources/le-staging-issuer.yaml b/base/cert-manager/resources/le-staging-issuer.yaml
deleted file mode 100644
index dd2356c..0000000
--- a/base/cert-manager/resources/le-staging-issuer.yaml
+++ /dev/null
@@ -1,18 +0,0 @@
-apiVersion: cert-manager.io/v1
-kind: ClusterIssuer
-metadata:
-  name: letsencrypt-staging
-spec:
-  acme:
-    # The ACME server URL
-    server: https://acme-staging-v02.api.letsencrypt.org/directory
-    # Email address used for ACME registration
-    email: adminfra@cadoles.com
-    # Name of a secret used to store the ACME account private key
-    privateKeySecretRef:
-      name: letsencrypt-staging
-    # Enable the HTTP-01 challenge provider
-    solvers:
-    - http01:
-        ingress:
-          ingressClassName: nginx