In order to study the electromagnetic and vibration performance of transformer under different tensile and compressive stresses. This paper firstly studies the magnetic properties of core silicon steel sheets for transformers under different tensile and compressive stresses, the B-H curves, B-P curves, and permeability curves of silicon steel sheets under different tensile and compressive stresses are given. Secondly, based on the test results of magnetic characteristics of the silicon steel sheet, the electromagnetic performance and vibration of a 3kVA transformer are simulated and analyzed. In the simulation process, the influence of different tensile and compressive stresses on the performance of the silicon steel sheet core of the transformer is considered. It provides a new idea for the electromagnetic-vibration analysis of transformers.