The invention discloses a welding deformation real-time detection system. The welding deformation real-time detection system is characterized by comprising a CCD camera (4), an environment light source (5), a detection module and a control module, the CCD camera (4) is used for generating a speckle field and forming speckle images on the surface of an irradiated welding workpiece, and then collecting the speckle images on all the stages of welding of the surface of the welding workpiece, the environment light source (5) is used for providing lighting of the surrounding of the welding workpiece when the speckle images are collected, the detection module is used for processing the collected speckle images, and recognizing three-dimensional coordinate changes of a deformation point, on the surface of the welding workpiece, on the speckle images according to the speckle images of all the stages so as to obtain a three-dimensional displacement field and a strain field of the surface of the welding workpiece, and the control module is used for providing electric power support for the CCD camera and having control over the image collection process. According to a detection method of the welding deformation real-time detection system, the cost is reduced, efficiency and accuracy are improved, and the great actual use value, and the economic and social benefits are achieved.