Cell migrations in the cell cultures are found to follow non-Gaussian statistics.We recorded long-term cell migration pattes with more than six hundred cells located in 28 mm2.Our experimental data support the claim that an individual cell migration follows Gaussian statistics.Because the cell culture is inhomogeneous,the statistics of the cell culture exhibit a non-Gaussian distribution.We find that the normalized histogram of the diffusion velocity follows an exponential tail.A simple model is proposed based on the diffusional inhomogeneity to explain the exponential distribution of locomotion activity in this work.Using numerical calculation,we prove that our model is in great agreement with the experimental data.