We propose a time variation channel estimation method for the Time Division Duplex-Long Term Evolution (TDD-LTE) uplink in the high speed train (HST) environment. In the transform domain, based on the estimated channel parameters of the two block pilots, the generalized complex exponential basis expansion model (GCE-BEM) is firstly employed to estimate the channel parameters of the data symbols between the two pilots. To avoid the expansion error at the subframe boundary caused by the Gibbs effect of the GCE-BEM, the decision-directed (DD) method is used to obtain the channel parameters of the data symbols out of the two pilots. Simulation results show that the performance of the proposed method is much better than those of the available methods, and it has a low computational complexity.