Abstract: Based on the structure characteristics of block-diagonal preconditioner and the idea of shift-splitting, a parameterized block shift-splitting preconditioner is proposed for solving a class of large sparse linear systems with 3×3 block structure, which is easy to implement and has high computational efficiency. Furthermore, the algorithm implementation is given, and the distribution range of non-zero eigenvalues of the corresponding preconditioned matrix and the algebraic multiplicity of eigenvalue 1 are discussed. Numerical experiments are illustrated to show the efficiency of the preconditioner.