The present invention discloses a massive multiple-input multiple-output (MIMO) beam domain robust precoding transmission method and system. The method is based on base station (BS)-side and user-side refined sampling steering vector matrices, and considers the influence of channel aging caused by mobility, where obtained channel state information is refined beam domain a posteriori statistical channel information including channel mean and variance information. In the present invention, the BS performs robust precoding transmission by using the refined beam domain a posteriori statistical channel information, where a channel model on which the adopted refined beam domain a posteriori statistical channel information depends is a channel model which corresponds to a refined sampling space angle and adopts a steering vector matrix; the used statistical channel information is more sufficient and accurate, so that the problem of universality of massive MIMO to various typical mobile scenarios under the condition that the antenna size is limited can be solved; and high spectral efficiency is achieved, and the provided robust precoding design utilizes the sparsity of a beam domain channel and the structural characteristics of a sampling steering vector matrix, so that the calculation complexity can be greatly reduced.