diff --git a/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_head.py b/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_head.py
index 6ed41265b7a..b133cd17a97 100644
--- a/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_head.py
+++ b/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_head.py
@@ -18,6 +18,7 @@
     unmap,
 )
 from otx.algo.modules.conv_module import ConvModule
+from otx.algo.modules.norm import is_norm
 from otx.algo.modules.scale import Scale
 from otx.algo.utils.mmengine_utils import InstanceData
 from otx.algo.utils.weight_init import bias_init_with_prob, constant_init, normal_init
@@ -108,7 +109,8 @@ def init_weights(self) -> None:
         for m in self.modules():
             if isinstance(m, nn.Conv2d):
                 normal_init(m, mean=0, std=0.01)
-            constant_init(m, 1)
+            if is_norm(m):
+                constant_init(m, 1)
         bias_cls = bias_init_with_prob(0.01)
         normal_init(self.rtm_cls, std=0.01, bias=bias_cls)
         normal_init(self.rtm_reg, std=0.01)
diff --git a/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_ins_head.py b/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_ins_head.py
index 7eec5dbeba0..743f5bbb279 100644
--- a/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_ins_head.py
+++ b/src/otx/algo/instance_segmentation/mmdet/models/dense_heads/rtmdet_ins_head.py
@@ -27,6 +27,7 @@
 from otx.algo.instance_segmentation.mmdet.structures.bbox.transforms import get_box_wh, scale_boxes
 from otx.algo.modules.base_module import BaseModule
 from otx.algo.modules.conv_module import ConvModule
+from otx.algo.modules.norm import is_norm
 from otx.algo.utils.weight_init import bias_init_with_prob, constant_init, normal_init
 
 from .rtmdet_head import RTMDetHead
@@ -912,7 +913,8 @@ def init_weights(self) -> None:
         for m in self.modules():
             if isinstance(m, nn.Conv2d):
                 normal_init(m, mean=0, std=0.01)
-            constant_init(m, 1)
+            if is_norm(m):
+                constant_init(m, 1)
         bias_cls = bias_init_with_prob(0.01)
         for rtm_cls, rtm_reg in zip(self.rtm_cls, self.rtm_reg):
             normal_init(rtm_cls, std=0.01, bias=bias_cls)
diff --git a/src/otx/algo/modules/norm.py b/src/otx/algo/modules/norm.py
index 587e6840ca8..88764f43585 100644
--- a/src/otx/algo/modules/norm.py
+++ b/src/otx/algo/modules/norm.py
@@ -132,3 +132,17 @@ def build_norm_layer(cfg: dict, num_features: int, postfix: int | str = "") -> t
         param.requires_grad = requires_grad
 
     return name, layer
+
+
+def is_norm(layer: nn.Module) -> bool:
+    """Check if a layer is a normalization layer.
+
+    Args:
+        layer (nn.Module): The layer to be checked.
+        exclude (type | tuple[type]): Types to be excluded.
+
+    Returns:
+        bool: Whether the layer is a norm layer.
+    """
+    all_norm_bases = (_BatchNorm, _InstanceNorm, nn.GroupNorm, nn.LayerNorm)
+    return isinstance(layer, all_norm_bases)