Lifting mechanism is an important part of Dump Truck's refitting structure. It directly related to the use of performance and overall arrangement. It was main factor which decided to dump automobile refitting design criterion. 3201Z-type dump trucks is adapted from the EQ3208GJ type truck chassis whose technical performance parameters is known. By means of analyzing and comparing several schemes, finally determined that oil cylinder former push type four connecting rod lifting mechanism suits 3201Z type dump trucks lifting mechanism. Analyzing the working principle of lifting mechanism, determination of lifting device geometry dimension and material, the selection of structure parameter, and through the application of the graphic method, mechanical lifting mechanism is analyzed and checked. Rationality and safety is checked on through the rod strength check computations and hinge pin shear and extruding strength check.