A control device for controlling a linear actuator having a linear motor and a brake device includes a magnetic pole position estimation means to estimate which of a plurality of sections obtained by dividing a magnetic pole position of 0° to 360°, the mover is located in on the basis of a direction of movement of the mover by pulse energization, a magnetic pole position setting means to perform direct current excitation at an estimated magnetic pole position estimated by the magnetic pole position estimation means and set the estimated magnetic pole position as a magnetic pole position of the mover, and a brake control means to turn on a brake device before pulse energization by the magnetic pole position estimation means is performed and turn off the brake device after the magnetic pole position estimation means estimates the section in which the mover is located.