diff --git a/Assets/Scripts/Mechanics/PlayerController.cs b/Assets/Scripts/Mechanics/PlayerController.cs
index f7485e5..bbe07a5 100644
--- a/Assets/Scripts/Mechanics/PlayerController.cs
+++ b/Assets/Scripts/Mechanics/PlayerController.cs
@@ -170,6 +170,12 @@ namespace Platformer.Mechanics
                     jumpState = JumpState.Jumping;
                     jump = true;
                     stopJump = false;
+                    // BT41 — PrepareToJump frame 영역 즉시 contactFilter Layer 16 mask OFF (다음 ComputeVelocity 영역 velocity.y 적용 영역 영역 frame 영역 발판 영역 충돌 차단)
+                    {
+                        int baseMaskJump = Physics2D.GetLayerCollisionMask(gameObject.layer);
+                        contactFilter.SetLayerMask(baseMaskJump & ~(1 << JUMP_THROUGH_LAYER));
+                        contactFilter.useLayerMask = true;
+                    }
                     break;
                 case JumpState.Jumping:
                     if (!IsGrounded)
@@ -197,7 +203,8 @@ namespace Platformer.Mechanics
         void UpdateContactFilterForDropThrough()
         {
             int baseMask = Physics2D.GetLayerCollisionMask(gameObject.layer);
-            bool ascending = velocity.y > 0.01f;
+            // BT41 — jumpState == Jumping 영역 영역 ascending true (PrepareToJump frame 직후 velocity.y 미반영 영역도 통과)
+            bool ascending = velocity.y > 0.01f || jumpState == JumpState.Jumping;
             int mask = ascending ? (baseMask & ~(1 << JUMP_THROUGH_LAYER)) : baseMask;
             contactFilter.SetLayerMask(mask);
             contactFilter.useLayerMask = true;