To effectively solve the large sparse linear equations of positive definite or positive semidefinite, the second stage splitting of generalized non-stationary multi-splitting two-stage iterative method is proposed, which combines the techniques of multi-splitting and matrix preprocessing generalizes the non-stationary multi-splitting two-stage iterative method based on the classical matrix splitting in the first stage. The algorithm and logical expression of the generalized non-stationary multi-stage iterative method are rewritten into a compact iterative scheme to consider the convergence. According to the iterative scheme, the generalized non-stationary multi-splitting two-stage iterative algorithm is convergent under a sufficient condition. Finally, a numerical example of a large sparse linear system with a five-diagonal coefficient matrix shows the feasibility of the generalized non-stationary multi-split two-stage iterative algorithm, and the efficiency of the algorithm is verified in terms of iteration steps and CPU time.