An object labeling system includes a first object labeling module, a second object label model, a label integrating module and an inter-frame tracking module. The first object label module is configured to generate a first object labeling result according to a first 2D image, wherein the first 2D image is one of the frames of a 2D video. The second object labeling module is configured to generate a second 2D image according to a 3D information, and to generate a second object labeling result according to the 3D information and the second 2D image. The label integrating is configured to generate a third object labeling result according to the first object labeling result and the second object labeling result. The inter-frame tracking module is configured to perform an inter-frame object labeling process according to the third object labeling result to generate a fourth object labeling result.