diff --git a/roles/kubernetes/master/templates/kubeadm-config.v1alpha1.yaml.j2 b/roles/kubernetes/master/templates/kubeadm-config.v1alpha1.yaml.j2
index e4dd7cbd..ec157e98 100644
--- a/roles/kubernetes/master/templates/kubeadm-config.v1alpha1.yaml.j2
+++ b/roles/kubernetes/master/templates/kubeadm-config.v1alpha1.yaml.j2
@@ -99,10 +99,10 @@ apiServerExtraArgs:
   oidc-groups-claim: {{ kube_oidc_groups_claim }}
 {%   endif %}
 {%   if kube_oidc_username_prefix is defined %}
-  oidc-username-prefix: {{ kube_oidc_username_prefix }}
+  oidc-username-prefix: "{{ kube_oidc_username_prefix }}"
 {%   endif %}
 {%   if kube_oidc_groups_prefix is defined %}
-  oidc-groups-prefix: {{ kube_oidc_groups_prefix }}
+  oidc-groups-prefix: "{{ kube_oidc_groups_prefix }}"
 {%   endif %}
 {% endif %}
 {% if kube_webhook_token_auth|default(false) %}
diff --git a/roles/kubernetes/master/templates/kubeadm-config.v1alpha2.yaml.j2 b/roles/kubernetes/master/templates/kubeadm-config.v1alpha2.yaml.j2
index 5663e8a7..6f9cd445 100644
--- a/roles/kubernetes/master/templates/kubeadm-config.v1alpha2.yaml.j2
+++ b/roles/kubernetes/master/templates/kubeadm-config.v1alpha2.yaml.j2
@@ -84,10 +84,10 @@ apiServerExtraArgs:
   oidc-groups-claim: {{ kube_oidc_groups_claim }}
 {%   endif %}
 {%   if kube_oidc_username_prefix is defined %}
-  oidc-username-prefix: {{ kube_oidc_username_prefix }}
+  oidc-username-prefix: "{{ kube_oidc_username_prefix }}"
 {%   endif %}
 {%   if kube_oidc_groups_prefix is defined %}
-  oidc-groups-prefix: {{ kube_oidc_groups_prefix }}
+  oidc-groups-prefix: "{{ kube_oidc_groups_prefix }}"
 {%   endif %}
 {% endif %}
 {% if kube_webhook_token_auth|default(false) %}
diff --git a/roles/kubernetes/master/templates/kubeadm-config.v1alpha3.yaml.j2 b/roles/kubernetes/master/templates/kubeadm-config.v1alpha3.yaml.j2
index 43ae27e5..6dc73665 100644
--- a/roles/kubernetes/master/templates/kubeadm-config.v1alpha3.yaml.j2
+++ b/roles/kubernetes/master/templates/kubeadm-config.v1alpha3.yaml.j2
@@ -94,10 +94,10 @@ apiServerExtraArgs:
   oidc-groups-claim: {{ kube_oidc_groups_claim }}
 {%   endif %}
 {%   if kube_oidc_username_prefix is defined %}
-  oidc-username-prefix: {{ kube_oidc_username_prefix }}
+  oidc-username-prefix: "{{ kube_oidc_username_prefix }}"
 {%   endif %}
 {%   if kube_oidc_groups_prefix is defined %}
-  oidc-groups-prefix: {{ kube_oidc_groups_prefix }}
+  oidc-groups-prefix: "{{ kube_oidc_groups_prefix }}"
 {%   endif %}
 {% endif %}
 {% if kube_webhook_token_auth|default(false) %}
diff --git a/roles/kubernetes/master/templates/kubeadm-config.v1beta1.yaml.j2 b/roles/kubernetes/master/templates/kubeadm-config.v1beta1.yaml.j2
index eec4f32f..0243ce38 100644
--- a/roles/kubernetes/master/templates/kubeadm-config.v1beta1.yaml.j2
+++ b/roles/kubernetes/master/templates/kubeadm-config.v1beta1.yaml.j2
@@ -91,10 +91,10 @@ apiServer:
     oidc-groups-claim: {{ kube_oidc_groups_claim }}
 {%   endif %}
 {%   if kube_oidc_username_prefix is defined %}
-    oidc-username-prefix: {{ kube_oidc_username_prefix }}
+    oidc-username-prefix: "{{ kube_oidc_username_prefix }}"
 {%   endif %}
 {%   if kube_oidc_groups_prefix is defined %}
-    oidc-groups-prefix: {{ kube_oidc_groups_prefix }}
+    oidc-groups-prefix: "{{ kube_oidc_groups_prefix }}"
 {%   endif %}
 {% endif %}
 {% if kube_webhook_token_auth|default(false) %}