To study and design the piezoresistive microphone, CoventorWareTM software package was used to simulate the response of diaphragm from the thickness of 0.1 μm to 0.5 μm, with surface dimension of 500*500, 1000*1000, 1500*1500, 2000*2000, 2500*2500 and 3000*3000 μm2. The sound pressure, used in the simulation, started from 20 μPa to 60 μPa ( 0 to 10 dB). The result will be used to determine the optimal position of strain gauges. From the simulated model, it can be seen that diaphragm experienced the highest stress at the egde, hence this is the most appropriate place for the resistor. The most appropriate dimensions are 3000 μm on each side with a thickness of 0.1 μm. With these dimensions, the calculated stress is the highest from all the different conditions used in the simulation. There will be two types of orientation used in placing the resistors: perpendicular and parallel to direction of the strain. The position for perpendicular placement is x, y e = 1500,y where y is in the range of 30 – 140 μm. The position for parallel placement is x, y e = x,0 where x is in the range of 1250 – 1750 μm.