diff --git a/src/core/border_router/routing_manager.cpp b/src/core/border_router/routing_manager.cpp
index d42648192..eabf9f4ac 100644
--- a/src/core/border_router/routing_manager.cpp
+++ b/src/core/border_router/routing_manager.cpp
@@ -405,8 +405,9 @@ void RoutingManager::EvaluateOmrPrefix(OmrPrefixArray &aNewOmrPrefixes)
 {
     NetworkData::Iterator           iterator = NetworkData::kIteratorInit;
     NetworkData::OnMeshPrefixConfig onMeshPrefixConfig;
-    Ip6::Prefix *                   smallestOmrPrefix       = nullptr;
-    Ip6::Prefix *                   publishedLocalOmrPrefix = nullptr;
+    Ip6::Prefix *                   electedOmrPrefix           = nullptr;
+    signed int                      electedOmrPrefixPreference = 0;
+    Ip6::Prefix *                   publishedLocalOmrPrefix    = nullptr;
 
     OT_ASSERT(mIsRunning);
 
@@ -431,9 +432,11 @@ void RoutingManager::EvaluateOmrPrefix(OmrPrefixArray &aNewOmrPrefixes)
             continue;
         }
 
-        if (smallestOmrPrefix == nullptr || (prefix < *smallestOmrPrefix))
+        if (electedOmrPrefix == nullptr || onMeshPrefixConfig.mPreference > electedOmrPrefixPreference ||
+            (onMeshPrefixConfig.mPreference == electedOmrPrefixPreference && prefix < *electedOmrPrefix))
         {
-            smallestOmrPrefix = aNewOmrPrefixes.Back();
+            electedOmrPrefix           = aNewOmrPrefixes.Back();
+            electedOmrPrefixPreference = onMeshPrefixConfig.mPreference;
         }
 
         if (prefix == mLocalOmrPrefix)
@@ -458,16 +461,16 @@ void RoutingManager::EvaluateOmrPrefix(OmrPrefixArray &aNewOmrPrefixes)
     }
     else
     {
-        OT_ASSERT(smallestOmrPrefix != nullptr);
+        OT_ASSERT(electedOmrPrefix != nullptr);
 
-        if (*smallestOmrPrefix == mLocalOmrPrefix)
+        if (*electedOmrPrefix == mLocalOmrPrefix)
         {
             IgnoreError(PublishLocalOmrPrefix());
         }
         else if (IsOmrPrefixAddedToLocalNetworkData())
         {
-            LogInfo("EvaluateOmrPrefix: There is already a smaller OMR prefix %s in the Thread network",
-                    smallestOmrPrefix->ToString().AsCString());
+            LogInfo("EvaluateOmrPrefix: There is already a preferred OMR prefix %s (pref=%d) in the Thread network",
+                    electedOmrPrefix->ToString().AsCString(), electedOmrPrefixPreference);
 
             UnpublishLocalOmrPrefix();
 
diff --git a/tests/scripts/thread-cert/border_router/test_manual_omr_prefix.py b/tests/scripts/thread-cert/border_router/test_manual_omr_prefix.py
index 62b1fd1a9..66f4cf2dd 100644
--- a/tests/scripts/thread-cert/border_router/test_manual_omr_prefix.py
+++ b/tests/scripts/thread-cert/border_router/test_manual_omr_prefix.py
@@ -79,21 +79,29 @@ class ManualOmrsPrefix(thread_cert.TestCase):
 
         # Add a smaller OMR prefix. Verify BR_1 withdraws its OMR prefix.
         self._test_manual_omr_prefix('2001::/64', 'paros', expect_withdraw=True)
+        # Add a bigger OMR prefix. Verify BR_1 does not withdraw its OMR prefix.
+        self._test_manual_omr_prefix('fdff:ffff:1::/64', 'paros', expect_withdraw=False, prf='med')
+        # Add a high preference bigger OMR prefix. Verify BR_1 withdraws its OMR prefix.
+        self._test_manual_omr_prefix('fdff:ffff:2::/64', 'paros', expect_withdraw=True, prf='high')
         # Add a smaller but invalid OMR prefix (P_on_mesh = 0). Verify BR_1 does not withdraw its OMR prefix.
         self._test_manual_omr_prefix('2002::/64', 'pars', expect_withdraw=False)
         # Add a smaller but invalid OMR prefix (P_stable = 0). Verify BR_1 does not withdraw its OMR prefix.
         self._test_manual_omr_prefix('2003::/64', 'paro', expect_withdraw=False)
 
-    def _test_manual_omr_prefix(self, prefix, flags, expect_withdraw):
+    def _test_manual_omr_prefix(self, prefix, flags, expect_withdraw, prf='med'):
         br1 = self.nodes[BR_1]
         br2 = self.nodes[BR_2]
 
-        br2.add_prefix(prefix, flags)
+        br2.add_prefix(prefix, flags, prf=prf)
         br2.register_netdata()
         self.simulator.go(10)
 
+        is_omr_prefix = ('a' in flags and 'o' in flags and 's' in flags and 'D' not in flags)
+
         if expect_withdraw:
             self._assert_prefixes_equal(br1.get_netdata_omr_prefixes(), [prefix])
+        elif is_omr_prefix:
+            self._assert_prefixes_equal(br1.get_netdata_omr_prefixes(), [br1.get_br_omr_prefix(), prefix])
         else:
             self._assert_prefixes_equal(br1.get_netdata_omr_prefixes(), [br1.get_br_omr_prefix()])