The present disclosure provides a robot-based 3D picture shooting method and system, and a robot using the same. The method includes: obtaining a distance between a photographed object and the photographing device of the robot based on a received shooting instruction; calculating an inter-axis distance based on the distance; obtaining the first picture after moving the robot for half of the inter-axis distance along the movement direction; obtaining the second picture after moving the robot for entire of the inter-axis distance from a current position along an opposite direction of the movement direction; and synthesizing the first picture and the second picture to obtain a 3D picture of the photographed object. In the process, the robot moves the photographing device according to the calculated inter-axis distance, and obtains two pictures of the left and right of the photographed object, which is not necessary to use a binocular camera.