Abstract: As a compact electron multiplier of high gain, microchannel plate (MCP) is widely used in particle and photon detection systems. MCP is intrinsically very fast detector. The pulse transmission time through the intense electric field is of order 10-10 second. The transmission process of the channel electron can be investigated by analytical method and Monte Carlo simulation respectively, but the dispersion of transmission time can not be explained with both methods. A statistical method is introduced to investigate the distribution characteristic of the crossing time during the transmission. The distribution function of the crossing time dispersion degree is obtained, i.e. the relationship between dispersion time and second multiplication times. The dispersion degree is dependent on the collision times.