This paper aim in design and analysis of MEMS Pressure Sensor by using ANSYS software. A diaphragm based MEMS sensor in the range of 25MPa by measured center deflection of the circular pressure-sensitive and using the strain gauge for measurement. First this paper created the mathematical calculation and then models the finite element analysis of the diaphragm using ANSYS and determined the pressure sensor in the range of 25MPa with circular diaphragm is designed, which also reflects the choice of correct design after analyzing the effect of diaphragm thickness, location and shapes of piezoresistor.