The bearing is very important segment in any rotating machinery. It is continually running under changing speed and load conditions. Failure of bearing frequently results in extensive mechanical downtime that has monetary outcomes. Timely diagnosis of bearing breakdown is to avoid machines failure, as well as to decrease the maintenance cost of machine. To analyze failure of the bearing artificial defect were created on various elements of the bearing and using vibration signature for monitoring its condition analysis is carried.In this paper the effect of various surface defects on the vibration response of outer race and inner race of the ball bearing and Roller bearing is discussed. Vibration spectrum produced by bearing with defect on inner or outer race under different load conditions is taken and effect of defect size and load on the vibration response has been investigated. Results are presented in time and frequency domain. The results obtained by experimentations are compared with MATLAB results