The embodiment of the invention provides a robot arm obstacle avoidance method and system. The method comprises the following steps: obtaining the measured distance value of an obstacle avoidance detector, corresponding to the current swing direction, on a robot arm according to the control to the current swing direction of the robot arm, which shows the distance between the robot arm and an obstacle in the current swing direction; controlling the robot arm to stop swinging to the current swing direction if the measured distance value is smaller than or equal to a preset obstacle avoidance distance threshold value, so as to realize obstacle avoidance of the robot arm in the current swing direction.