This invention discloses a blood pressure measurement device including a cuff having a bladder wrap around an object to be measured, a MEMS pump for inflating the bladder with air, a pressure sensor for monitoring the pressure in the bladder, and a microcontroller for controlling the pressure sensor to continuously receive pressure signals during the process of inflating the bladder, converting the pressure signals into blood pressure values, and controlling a drive voltage level of the MEMS pump to maintain an air inflation speed of the MEMS pump in a predetermined inflation speed range. The invention further discloses a method for controlling a fixed frequency change of the blood pressure measurement device.