diff --git a/data/templates/ocserv/ocserv_config.j2 b/data/templates/ocserv/ocserv_config.j2
index 81f7770314..76d3e6e4ee 100644
--- a/data/templates/ocserv/ocserv_config.j2
+++ b/data/templates/ocserv/ocserv_config.j2
@@ -30,6 +30,15 @@ auth = "plain[otp=/run/ocserv/users.oath]"
 {%     else %}
 auth = "plain[/run/ocserv/ocpasswd]"
 {%     endif %}
+{% elif "certificate" in authentication.mode %}
+auth = "certificate"
+{%     if authentication.mode.certificate.user_identifier_field == "cn" %}
+cert-user-oid = 2.5.4.3
+{%     elif authentication.mode.certificate.user_identifier_field == "uid" %}
+cert-user-oid = 0.9.2342.19200300.100.1.1
+{%     else %}
+cert-user-oid = {{ authentication.mode.certificate.user_identifier_field }}
+{%     endif %}
 {% else %}
 auth = "plain[/run/ocserv/ocpasswd]"
 {% endif %}
diff --git a/interface-definitions/vpn_openconnect.xml.in b/interface-definitions/vpn_openconnect.xml.in
index a2f040b2fa..085f181fdd 100644
--- a/interface-definitions/vpn_openconnect.xml.in
+++ b/interface-definitions/vpn_openconnect.xml.in
@@ -69,6 +69,37 @@
                       <valueless/>
                     </properties>
                   </leafNode>
+                  <node name="certificate">
+                    <properties>
+                      <help>Use certificate based authentication</help>
+                    </properties>
+                    <children>
+                      <leafNode name="user-identifier-field">
+                        <properties>
+                          <help>Defines what field in the certificate identifies the username</help>
+                          <valueHelp>
+                            <format>cn</format>
+                            <description>OID 2.5.4.3 - Common Name</description>
+                          </valueHelp>
+                          <valueHelp>
+                            <format>uid</format>
+                            <description>OID 0.9.2342.19200300.100.1.1 - UID</description>
+                          </valueHelp>
+                          <valueHelp>
+                            <format>x.x.xx.xxx</format>
+                            <description>Custom OID in dotted decimal format</description>
+                          </valueHelp>
+                          <constraint>
+                            <regex>(^\d{1,5}(?:\.\d{1,5})*$|cn|uid)</regex>
+                          </constraint>
+                          <constraintErrorMessage>Invalid OID selection. Must be cn, uid, or a valid OID format.</constraintErrorMessage>
+                          <completionHelp>
+                            <list>cn uid x.x.xx.xxx</list>
+                          </completionHelp>
+                         </properties>
+                       </leafNode>
+                     </children>
+                   </node>
                 </children>
               </node>
               <node name="identity-based-config">
diff --git a/src/conf_mode/vpn_openconnect.py b/src/conf_mode/vpn_openconnect.py
index 68cd363f08..8522a325bb 100755
--- a/src/conf_mode/vpn_openconnect.py
+++ b/src/conf_mode/vpn_openconnect.py
@@ -105,11 +105,17 @@ def verify(ocserv):
     if 'authentication' in ocserv:
         if 'mode' in ocserv['authentication']:
             if (
-                'local' in ocserv['authentication']['mode']
-                and 'radius' in ocserv['authentication']['mode']
+                ('local' in ocserv['authentication']['mode']
+                 and 'radius' in ocserv['authentication']['mode'])
+                or
+                ('local' in ocserv['authentication']['mode']
+                 and 'certificate' in ocserv['authentication']['mode'])
+                or
+                ('radius' in ocserv['authentication']['mode']
+                 and 'certificate' in ocserv['authentication']['mode'])
             ):
                 raise ConfigError(
-                    'OpenConnect authentication modes are mutually-exclusive, remove either local or radius from your configuration'
+                    'OpenConnect authentication modes are mutually-exclusive. Only one of local, radius, or certificate.'
                 )
             if 'radius' in ocserv['authentication']['mode']:
                 if 'server' not in ocserv['authentication']['radius']:
@@ -203,6 +209,9 @@ def verify(ocserv):
         raise ConfigError('SSL certificate missing on OpenConnect config!')
     verify_pki_certificate(ocserv, ocserv['ssl']['certificate'])
 
+    if 'ca_certificate' not in ocserv['ssl'] and 'certificiate' in ocserv['authentication']['mode']:
+        raise ConfigError('CA certificate must be provided in certificate authentication mode!')
+
     if 'ca_certificate' in ocserv['ssl']:
         for ca_cert in ocserv['ssl']['ca_certificate']:
             verify_pki_ca_certificate(ocserv, ca_cert)