Metropolis molecular dynamics simulation combined with bond-fluctuation method was employed to study the dynamic process of single DNA chain through an entropic trapping channel driven by an electric field. It was found that the single DNA chain experienced the processes such as random transfer, entropic trapping and fast transfer etc. The mobility of DNA increased with the increase of electric field and reached the conformation-independent mobility μ0 at a high electric field. In particular, a clear linear relationship between lnτ and 1/Eav (the reciprocal of electric field) could be seen. The simulation result was in agreement with the experimental result presented by Han et al qualitatively. In addition, the simulation provided a detailed dynamic process of the single DNA chain driven through an entropic trapping channel,which could not be observed in the experiment.