This paper gives an efficient approach to reconstruct moving multiple objects (multi-object).Each object has independently rigid motion which includes translation and rotation.The traditional FBP algorithm can resolve the one-object motion problem rather well.However,it suffers from perceptible motion artifacts in multi-object cases.This paper proposes a new motion-compensated reconstruction approach with a priod knowledge of the rigid motion model.Both an FBP-type and an ART-type algorithm were derived.In an effort to evaluate the proposed algorithms,we have performed numerical studies by using different rigid motion models.Quantitative results demonstrate that the proposed FBP-type and ART-type algorithms can reconstruct multi-object free of motion artifacts.