Komatsu (2000 a，b) reported the description of perceptual causal-ity in the tunnel effect. In his experiments， the moving object appeared in front ofthe still object， as soon as the whole of moving object was by a still object. Someobservers perceived that the moving object before occlusion was different fromthe moving object after occlusion. And they often perceived the causal relationamong the objects. (1)When the moving object passed behind the still object and the speed of themoving object before occlusion was same as the moving object after occlusion，observers perceived the first was identical with the second. When the second wasslower than the first， observers perceived the second object moved by itself， exceptthe case that the E-E interval (Entrance-Exit interval， the duration for which themoving object is totally hidden by the still object) was O.7s. (2)When the moving object suddenly appeared in front of the still object afterthe moving object was occluded by the still object， observers perceived that thesecond was different from the first， and the second moved by itself in most cases. (3)When the second object was in front of the still object from the beginning andit started to move after the first object disappeared behind the still object and theE-Einterval was short， the second object was moved by the first.