diff --git a/Assets/Scripts/Mechanics/PlayerController.cs b/Assets/Scripts/Mechanics/PlayerController.cs
index 5fc89c7..d4af670 100644
--- a/Assets/Scripts/Mechanics/PlayerController.cs
+++ b/Assets/Scripts/Mechanics/PlayerController.cs
@@ -146,8 +146,18 @@ namespace Platformer.Mechanics
                 if (jumpState == JumpState.Grounded && m_JumpAction.WasPressedThisFrame())
                 {
                     // BT69 — Down + Jump = Drop-Through (PD 명시 2026-05-08)
+                    // BT70 — 발판(Layer 16) 위 검증 추가 (PD 보고 2026-05-08: 지면 위 Down + Jump = 점프 X 버그)
+                    //         발판 위만 Drop-Through 발동·지면 위 = 일반 점프
                     bool downHeld = moveInput.y < -0.5f;
-                    if (downHeld)
+                    bool onJumpThroughPlatform = false;
+                    if (downHeld && collider2d != null)
+                    {
+                        Vector2 dropFootPos = new Vector2(collider2d.bounds.center.x, collider2d.bounds.min.y + 0.02f);
+                        int jumpThroughMask = 1 << JUMP_THROUGH_LAYER;
+                        RaycastHit2D dropFootHit = Physics2D.Raycast(dropFootPos, Vector2.down, 0.1f, jumpThroughMask);
+                        onJumpThroughPlatform = dropFootHit.collider != null;
+                    }
+                    if (downHeld && onJumpThroughPlatform)
                     {
                         dropThroughTimer = DROP_THROUGH_DURATION;
                         dropThroughJump = true;