This paper introduces the development process of a surface acoustic wave(SAW) filter for Band3 receiver, In order to satisfy the large-bandwidth performance of the filter and the high selectivity at the low end of the stopband, a 7-interdigital transducer(7-IDT) hybrid structure is used, and the coupling of mode model is used for automatic optimization design and multiple optimization iterations, And use finite element method/boundary element method(FEM/BEM) software to carry out accurate acoustic verification, and finally through the test to verify the effectiveness of the simulation results,