An elevation adaptive algorithm is presented according to the characteristics that clutter Doppler varies with range in airborne phased array radar. This algorithm, by making use of the elevation freedom in plane array antenna, is first to select the training data from Doppler cells in the short-range clutter region to evaluate the covariance matrix, and then to calculate the elevation optimum weight. When the PRF is chosen so that radar is range ambiguous, this algorithm can eliminate short-range clutter while reserving the long-range clutter. Thus, the clutter range dependence is alleviated, which is of great help for latter STAP in azimuth and time domain.