diff --git a/src/sonic-yang-models/tests/files/sample_config_db.json b/src/sonic-yang-models/tests/files/sample_config_db.json
index f75a8602fc10..353c26096b37 100644
--- a/src/sonic-yang-models/tests/files/sample_config_db.json
+++ b/src/sonic-yang-models/tests/files/sample_config_db.json
@@ -1597,7 +1597,7 @@
         "BGP_MONITORS": {
             "5.6.7.8": {
                 "admin_status": "up",
-                "asn": "65000",
+                "asn": "0",
                 "holdtime": "180",
                 "keepalive": "60",
                 "local_addr": "10.0.0.11",
diff --git a/src/sonic-yang-models/yang-models/sonic-bgp-common.yang b/src/sonic-yang-models/yang-models/sonic-bgp-common.yang
index 9e3d1638b25a..e035c1be261c 100644
--- a/src/sonic-yang-models/yang-models/sonic-bgp-common.yang
+++ b/src/sonic-yang-models/yang-models/sonic-bgp-common.yang
@@ -534,7 +534,7 @@ module sonic-bgp-common {
     grouping sonic-bgp-cmn-neigh {
         leaf asn {
             type uint32 {
-                range "1..4294967295";
+                range "0..4294967295";
             }
             description "Peer AS number";
         }
diff --git a/src/sonic-yang-models/yang-models/sonic-bgp-internal-neighbor.yang b/src/sonic-yang-models/yang-models/sonic-bgp-internal-neighbor.yang
index a58f404cb693..163a6aaed374 100644
--- a/src/sonic-yang-models/yang-models/sonic-bgp-internal-neighbor.yang
+++ b/src/sonic-yang-models/yang-models/sonic-bgp-internal-neighbor.yang
@@ -43,6 +43,9 @@ module sonic-bgp-internal-neighbor {
                         must "(current() = /dm:sonic-device_metadata/dm:DEVICE_METADATA/dm:localhost/dm:bgp_asn)" {
                             error-message "Internal iBGP neighbors should have same ASN as defined in device metadata";
                         }
+                        must ". >= 1" {
+                            error-message "ASN must be greater than 0";
+                        }
                     }
                     refine local_addr {
                         mandatory true;
diff --git a/src/sonic-yang-models/yang-models/sonic-bgp-neighbor.yang b/src/sonic-yang-models/yang-models/sonic-bgp-neighbor.yang
index a48b4228637a..c8ce6ec4adf3 100644
--- a/src/sonic-yang-models/yang-models/sonic-bgp-neighbor.yang
+++ b/src/sonic-yang-models/yang-models/sonic-bgp-neighbor.yang
@@ -61,7 +61,13 @@ module sonic-bgp-neighbor {
                     description "BGP Neighbor address";
                 }
 
-                uses bgpcmn:sonic-bgp-cmn-neigh;
+                uses bgpcmn:sonic-bgp-cmn-neigh {
+                    refine asn {
+                        must ". >= 1" {
+                            error-message "ASN must be greater than 0";
+                        }
+                    }
+                }
             }
 
             list BGP_NEIGHBOR_LIST {
diff --git a/src/sonic-yang-models/yang-models/sonic-bgp-voq-chassis-neighbor.yang b/src/sonic-yang-models/yang-models/sonic-bgp-voq-chassis-neighbor.yang
index ad4d227ee0a8..db7088ecc312 100644
--- a/src/sonic-yang-models/yang-models/sonic-bgp-voq-chassis-neighbor.yang
+++ b/src/sonic-yang-models/yang-models/sonic-bgp-voq-chassis-neighbor.yang
@@ -45,6 +45,9 @@ module sonic-bgp-voq-chassis-neighbor {
                         must "(current() = /dm:sonic-device_metadata/dm:DEVICE_METADATA/dm:localhost/dm:bgp_asn)" {
                             error-message "Voq chassis BGP neighbors should have same ASN as defined in device metadata";
                         }
+                        must ". >= 1" {
+                            error-message "ASN must be greater than 0";
+                        }
                     }
                     refine local_addr {
                         mandatory true;