A drive apparatus for an ultrasonic device includes a transmission circuit for outputting a first through n-th (where n is an integer 2 or greater) drive signal to first through n-th driving electrode line belonging to the ultrasonic device, as well as a control unit for controlling the transmission circuit. In a case where the phase difference between an i-th (where i is an integer 1≦i≦n−1) drive signal and an i+1-th drive signal is a first phase difference, the transmission circuit outputs the first through n-th drive signals at a greater voltage amplitude than a case where the phase difference between the i-th drive signal and the i+1-th drive signal is a second phase difference greater than the first phase difference.