The present disclosure discloses an ultrasonic fingerprint sensor. The ultrasonic fingerprint sensor includes a piezoelectric layer, a number of emitters, and a number of receiving electrode lines. The piezoelectric layer includes an array of piezoelectric posts. The emitters are formed on a lower end of the piezoelectric layer and correspond to the piezoelectric posts. Each of the emitters is connected to a corresponding piezoelectric post. The receiving electrode lines are arranged on an upper end of the piezoelectric layer, and each of the receiving electrode lines corresponds to a row of the piezoelectric posts and connected to the row of the piezoelectric posts. The present disclosure also discloses a fingerprint recognition module.