diff --git a/doc/SAI-IPv6-Segment-Routing-VPN.md b/doc/SAI-IPv6-Segment-Routing-VPN.md
index 316e4fe33..6333f416c 100644
--- a/doc/SAI-IPv6-Segment-Routing-VPN.md
+++ b/doc/SAI-IPv6-Segment-Routing-VPN.md
@@ -664,6 +664,63 @@ has a NULL object id for SID-list.
     saistatus = sai_route_api->create_route(&route_entry, 2, route_entry_attrs);
 ```
 
+## SRv6 SID Marking Feature
+
+This section describes the SID Marking feature for SRv6 VPN, which enables VPN SIDs to carry QoS and policy information derived from packet classification. Two new tunnel map types support SID Marking by allowing VPN SID selection based on forwarding class (which is mapped from DSCP via QoS Maps or ACL classification) and hierarchical policy lookup.
+
+### SAI_TUNNEL_MAP_TYPE_FORWARDING_CLASS_TO_SRV6_VPN_SID - SID Marking
+
+#### Overview
+
+The `SAI_TUNNEL_MAP_TYPE_FORWARDING_CLASS_TO_SRV6_VPN_SID` tunnel map type implements the core SID Marking capability. It enables VPN SIDs to be "marked" with QoS information by selecting different VPN SIDs based on forwarding class. The forwarding class is derived from packet DSCP values through QoS Map classification or ACL-based classification, allowing the ingress node to encode traffic priority directly into the VPN SID itself. This marked VPN SID then carries the QoS information end-to-end through the SRv6 network.
+
+#### API Attributes
+
+**Tunnel Map Type:**
+```c
+SAI_TUNNEL_MAP_TYPE_FORWARDING_CLASS_TO_SRV6_VPN_SID = 0x0000000f
+```
+
+**Tunnel Map Entry Attributes:**
+```c
+// Key: Forwarding Class
+SAI_TUNNEL_MAP_ENTRY_ATTR_FORWARDING_CLASS_KEY = 0x00000013
+// Type: sai_uint32_t
+// Flags: MANDATORY_ON_CREATE | CREATE_ONLY
+
+// Value: SRv6 VPN SID
+SAI_TUNNEL_MAP_ENTRY_ATTR_SRV6_VPN_SID_VALUE = 0x00000011
+// Type: sai_ip6_t
+// Flags: MANDATORY_ON_CREATE | CREATE_ONLY
+```
+
+### SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_TUNNEL_MAP_ID - Hierarchical SID Marking
+
+#### Overview
+
+The `SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_TUNNEL_MAP_ID` tunnel map type enables hierarchical, two-level lookup for VPN SID selection. This indirection allows combining the prefix-based derivation with the forwarding-class-based SID Marking.
+
+#### API Attributes
+
+**Tunnel Map Type:**
+```c
+SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_TUNNEL_MAP_ID = 0x0000000e
+```
+
+**Tunnel Map Entry Attributes:**
+```c
+// Key: Prefix Aggregation ID
+SAI_TUNNEL_MAP_ENTRY_ATTR_PREFIX_AGG_ID_KEY = 0x00000010
+// Type: sai_uint32_t
+// Flags: MANDATORY_ON_CREATE | CREATE_ONLY
+
+// Value: Tunnel Map Object ID
+SAI_TUNNEL_MAP_ENTRY_ATTR_TUNNEL_MAP_ID_VALUE = 0x00000012
+// Type: sai_object_id_t
+// Flags: MANDATORY_ON_CREATE | CREATE_ONLY
+// Objects: SAI_OBJECT_TYPE_TUNNEL_MAP
+```
+
 ## References
 1. [IPv6 Segment Routing Header (SRH)](https://tools.ietf.org/html/rfc8754)
 2. [Segment Routing over IPv6 (SRv6) Network Programming](https://tools.ietf.org/html/rfc8986)
diff --git a/inc/saitunnel.h b/inc/saitunnel.h
index 1b7aaa968..0b9d3df3f 100644
--- a/inc/saitunnel.h
+++ b/inc/saitunnel.h
@@ -80,6 +80,12 @@ typedef enum _sai_tunnel_map_type_t
     /** TUNNEL Map Prefix Aggregation ID to SRV6 VPN SID */
     SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_SRV6_VPN_SID = 0x0000000d,
 
+    /** TUNNEL Map Prefix Aggregation ID to Tunnel Map ID */
+    SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_TUNNEL_MAP_ID = 0x0000000e,
+
+    /** TUNNEL Map Forwarding Class to SRV6 VPN SID */
+    SAI_TUNNEL_MAP_TYPE_FORWARDING_CLASS_TO_SRV6_VPN_SID = 0x0000000f,
+
     /** Custom range base value */
     SAI_TUNNEL_MAP_TYPE_CUSTOM_RANGE_BASE = 0x10000000
 
@@ -259,6 +265,25 @@ typedef enum _sai_tunnel_map_entry_attr_t
      */
     SAI_TUNNEL_MAP_ENTRY_ATTR_SRV6_VPN_SID_VALUE = 0x00000011,
 
+    /**
+     * @brief Tunnel Map ID value
+     *
+     * @type sai_object_id_t
+     * @flags MANDATORY_ON_CREATE | CREATE_ONLY
+     * @objects SAI_OBJECT_TYPE_TUNNEL_MAP
+     * @condition SAI_TUNNEL_MAP_ENTRY_ATTR_TUNNEL_MAP_TYPE == SAI_TUNNEL_MAP_TYPE_PREFIX_AGG_ID_TO_TUNNEL_MAP_ID
+     */
+    SAI_TUNNEL_MAP_ENTRY_ATTR_TUNNEL_MAP_ID_VALUE = 0x00000012,
+
+    /**
+     * @brief Forwarding Class value
+     *
+     * @type sai_uint32_t
+     * @flags MANDATORY_ON_CREATE | CREATE_ONLY
+     * @condition SAI_TUNNEL_MAP_ENTRY_ATTR_TUNNEL_MAP_TYPE == SAI_TUNNEL_MAP_TYPE_FORWARDING_CLASS_TO_SRV6_VPN_SID
+     */
+    SAI_TUNNEL_MAP_ENTRY_ATTR_FORWARDING_CLASS_KEY = 0x00000013,
+
     /**
      * @brief End of attributes
      */