We propose a method to estimate the output of strain sensors which are burried in an elastic body such as silicone rubber(PDMS) when a certain force is applied onto the surface of the elastic body. Using the theoretical stresses occur inside the elastic body, we calculated the displacement at the point where a strain sensor is burried and then estimated the output of the sensor. We also compared the calculated displacement with ANSYS result and estimated output with actual output of the strain sensors.