diff --git a/pycti/api/opencti_api_client.py b/pycti/api/opencti_api_client.py
index 07826224f..bbde7d68b 100644
--- a/pycti/api/opencti_api_client.py
+++ b/pycti/api/opencti_api_client.py
@@ -71,6 +71,25 @@
 from pycti.utils.opencti_stix2_utils import OpenCTIStix2Utils
 
 
+def build_request_headers(token: str, custom_headers: str, app_logger):
+    headers_dict = {
+        "User-Agent": "pycti/" + __version__,
+        "Authorization": "Bearer " + token,
+    }
+    # Build and add custom headers
+    if custom_headers is not None:
+        for header_pair in custom_headers.strip().split(";"):
+            if header_pair:  # Skip empty header pairs
+                try:
+                    key, value = header_pair.split(":", 1)
+                    headers_dict[key.strip()] = value.strip()
+                except ValueError:
+                    app_logger.warning(
+                        "Ignored invalid header pair", {"header_pair": header_pair}
+                    )
+    return headers_dict
+
+
 class File:
     def __init__(self, name, data, mime="text/plain"):
         self.name = name
@@ -99,24 +118,28 @@ class OpenCTIApiClient:
         ```
     :param json_logging: format the logs as json if set to True
     :type json_logging: bool, optional
+    :param bundle_send_to_queue: if bundle will be sent to queue
+    :type bundle_send_to_queue: bool, optional
     :param cert: If String, file path to pem file. If Tuple, a ('path_to_cert.crt', 'path_to_key.key') pair representing the certificate and the key.
     :type cert: str, tuple, optional
-    :param auth: Add a AuthBase class with custom authentication for you OpenCTI infrastructure.
-    :type auth: requests.auth.AuthBase, optional
+    :param custom_headers: Add custom headers to use with the graphql queries
+    :type custom_headers: str, optional must in the format header01:value;header02:value
+    :param perform_health_check: if client init must check the api access
+    :type perform_health_check: bool, optional
     """
 
     def __init__(
         self,
         url: str,
         token: str,
-        log_level="info",
+        log_level: str = "info",
         ssl_verify: Union[bool, str] = False,
         proxies: Union[Dict[str, str], None] = None,
-        json_logging=False,
-        bundle_send_to_queue=True,
+        json_logging: bool = False,
+        bundle_send_to_queue: bool = True,
         cert: Union[str, Tuple[str, str], None] = None,
-        auth=None,
-        perform_health_check=True,
+        custom_headers: str = None,
+        perform_health_check: bool = True,
     ):
         """Constructor method"""
 
@@ -138,17 +161,10 @@ def __init__(
         # Define API
         self.api_token = token
         self.api_url = url + "/graphql"
-        self.request_headers = {
-            "User-Agent": "pycti/" + __version__,
-            "Authorization": "Bearer " + token,
-        }
-
-        if auth is not None:
-            self.session = requests.session()
-            self.session.auth = auth
-        else:
-            self.session = requests.session()
-
+        self.request_headers = build_request_headers(
+            token, custom_headers, self.app_logger
+        )
+        self.session = requests.session()
         # Define the dependencies
         self.work = OpenCTIApiWork(self)
         self.playbook = OpenCTIApiPlaybook(self)
diff --git a/pycti/connector/opencti_connector_helper.py b/pycti/connector/opencti_connector_helper.py
index 5a187126f..2b157c676 100644
--- a/pycti/connector/opencti_connector_helper.py
+++ b/pycti/connector/opencti_connector_helper.py
@@ -902,6 +902,12 @@ def __init__(self, config: Dict, playbook_compatible=False) -> None:
         self.opencti_token = get_config_variable(
             "OPENCTI_TOKEN", ["opencti", "token"], config
         )
+        self.opencti_custom_headers = get_config_variable(
+            "OPENCTI_CUSTOM_HEADERS",
+            ["opencti", "custom_headers"],
+            config,
+            default=None,
+        )
         self.opencti_ssl_verify = get_config_variable(
             "OPENCTI_SSL_VERIFY", ["opencti", "ssl_verify"], config, False, False
         )
@@ -1078,6 +1084,7 @@ def __init__(self, config: Dict, playbook_compatible=False) -> None:
             self.log_level,
             self.opencti_ssl_verify,
             json_logging=self.opencti_json_logging,
+            custom_headers=self.opencti_custom_headers,
             bundle_send_to_queue=self.bundle_send_to_queue,
         )
         # - Impersonate API that will use applicant id
@@ -1088,6 +1095,7 @@ def __init__(self, config: Dict, playbook_compatible=False) -> None:
             self.log_level,
             self.opencti_ssl_verify,
             json_logging=self.opencti_json_logging,
+            custom_headers=self.opencti_custom_headers,
             bundle_send_to_queue=self.bundle_send_to_queue,
         )
         self.connector_logger = self.api.logger_class(self.connect_name)