A teaching method includes imaging a teaching jig to acquire a captured image, detecting a position and a posture of the teaching jig based on the captured image, changing a position and a posture of a robot arm of a robot based on a result obtained by the detection to maintain a positional relation between the teaching jig and a control point of the robot arm, and acquiring the position and the posture of the robot arm as teaching information when a control device, which controls operation of the robot, acquires a teaching signal.