diff --git a/components/apimgt/org.wso2.carbon.apimgt.common.gateway/src/main/java/org/wso2/carbon/apimgt/common/gateway/jwtgenerator/AbstractAPIMgtGatewayJWTGenerator.java b/components/apimgt/org.wso2.carbon.apimgt.common.gateway/src/main/java/org/wso2/carbon/apimgt/common/gateway/jwtgenerator/AbstractAPIMgtGatewayJWTGenerator.java
index 35877ed2ad4c..743548c826fc 100644
--- a/components/apimgt/org.wso2.carbon.apimgt.common.gateway/src/main/java/org/wso2/carbon/apimgt/common/gateway/jwtgenerator/AbstractAPIMgtGatewayJWTGenerator.java
+++ b/components/apimgt/org.wso2.carbon.apimgt.common.gateway/src/main/java/org/wso2/carbon/apimgt/common/gateway/jwtgenerator/AbstractAPIMgtGatewayJWTGenerator.java
@@ -22,6 +22,8 @@
 import com.nimbusds.jwt.JWTClaimsSet;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.json.JSONException;
+import org.json.JSONObject;
 import org.wso2.carbon.apimgt.common.gateway.constants.JWTConstants;
 import org.wso2.carbon.apimgt.common.gateway.dto.JWTConfigurationDto;
 import org.wso2.carbon.apimgt.common.gateway.dto.JWTInfoDto;
@@ -107,25 +109,21 @@ public String buildHeader() throws JWTGeneratorException {
         String jwtHeader = null;
         X509Certificate x509Certificate = (X509Certificate) jwtConfigurationDto.getPublicCert();
 
-        if (NONE.equals(signatureAlgorithm)) {
-            StringBuilder jwtHeaderBuilder = new StringBuilder();
-            jwtHeaderBuilder.append("{\"typ\":\"JWT\",");
-            jwtHeaderBuilder.append("\"alg\":\"");
-            jwtHeaderBuilder.append(JWTUtil.getJWSCompliantAlgorithmCode(NONE));
-            jwtHeaderBuilder.append('\"');
-            if (jwtConfigurationDto.useKid()) {
-                jwtHeaderBuilder.append(",\"kid\":\"");
-                jwtHeaderBuilder.append(JWTUtil.getKID(x509Certificate));
-                jwtHeaderBuilder.append("\"");
+        try {
+            if (NONE.equals(signatureAlgorithm)) {
+                JSONObject jwtHeaderBuilder = new JSONObject();
+                jwtHeaderBuilder.put("typ", "JWT");
+                jwtHeaderBuilder.put("alg", JWTUtil.getJWSCompliantAlgorithmCode(NONE));
+                if (jwtConfigurationDto.useKid()) {
+                    jwtHeaderBuilder.put("kid", JWTUtil.getKID(x509Certificate));
+                }
+                jwtHeader = jwtHeaderBuilder.toString();
+            } else if (SHA256_WITH_RSA.equals(signatureAlgorithm)) {
+                jwtHeader = addCertToHeader();
             }
-            jwtHeaderBuilder.append('}');
-
-            jwtHeader = jwtHeaderBuilder.toString();
-
-        } else if (SHA256_WITH_RSA.equals(signatureAlgorithm)) {
-            jwtHeader = addCertToHeader();
-        }
-        return jwtHeader;
+        } catch (JSONException e) {
+            throw new JWTGeneratorException("Encountered an error while generating JWT header json object", e);
+        } return jwtHeader;
     }
 
     public byte[] signJWT(String assertion) throws JWTGeneratorException {
diff --git a/components/apimgt/org.wso2.carbon.apimgt.keymgt/src/main/java/org/wso2/carbon/apimgt/keymgt/token/AbstractJWTGenerator.java b/components/apimgt/org.wso2.carbon.apimgt.keymgt/src/main/java/org/wso2/carbon/apimgt/keymgt/token/AbstractJWTGenerator.java
index 9cec54d0b277..f4d725bc252c 100644
--- a/components/apimgt/org.wso2.carbon.apimgt.keymgt/src/main/java/org/wso2/carbon/apimgt/keymgt/token/AbstractJWTGenerator.java
+++ b/components/apimgt/org.wso2.carbon.apimgt.keymgt/src/main/java/org/wso2/carbon/apimgt/keymgt/token/AbstractJWTGenerator.java
@@ -189,15 +189,10 @@ public String buildHeader(String tenantDomain) throws APIManagementException {
 
         //if signature algo==NONE, header without cert
         if (NONE.equals(signatureAlgorithm)) {
-            StringBuilder jwtHeaderBuilder = new StringBuilder();
-            jwtHeaderBuilder.append("{\"typ\":\"JWT\",");
-            jwtHeaderBuilder.append("\"alg\":\"");
-            jwtHeaderBuilder.append(APIUtil.getJWSCompliantAlgorithmCode(NONE));
-            jwtHeaderBuilder.append('\"');
-            jwtHeaderBuilder.append('}');
-
+            JSONObject jwtHeaderBuilder = new JSONObject();
+            jwtHeaderBuilder.put("typ", "JWT");
+            jwtHeaderBuilder.put("alg", APIUtil.getJWSCompliantAlgorithmCode(NONE));
             jwtHeader = jwtHeaderBuilder.toString();
-
         } else if (SHA256_WITH_RSA.equals(signatureAlgorithm)) {
             jwtHeader = addCertToHeader(tenantDomain);
         }