Based on the structural topology optimization idea, a structural material optimization method with varying frequency interval constraints was proposed to solve the problem of structural material optimization with frequency constraints. By use of homogenization and ICM (Independent Continuous and Mapping) method, the effective mass matrix and its derivatives were established through taking the reciprocal topological variables of micro structural elements as design variables, and the one order approximate explicit functions of frequency interval constraints were constructed. Integrated with the idea of varying frequency interval constraints, a topological optimization model of micro structures was formed by taking the structural mass as objective function and the frequency as constraint functions. Then, a dual solving method was adopted. Two example results show that the proposed method is feasible and effective, and the optimal result obtained by the proposed method in which the change quantities of the mass matrix is considered, are more reasonable.