Clamping and lifting mechanism is the part of towbarless aircraft tractor directly connected with aircraft, which is needed to clamp wheel and lift it off the ground. Schematic diagram of common clamping and lifting mechanisms was established, degree of freedom (DOF) for the mechanisms was calculated with KutzbachGrübler formula. The motion equations of position and orientation were established with DenavitHartenberg (DH) transformation matrix as a tool of modeling. Its analytical positive solution was acquired, and the theoretical velocity expression was acquired by analytical method. The result indicates that number of DOF is the same as number of active driving parts of the mechanism, which have exclusive determined movements. Position and orientation expression in DH transformation matrix method is same with geometric, and the simulation result of angular transformation is approximately the same as theoretical calculation value, which proves validity of the mechanism. Whats more, it provides a reference for innovative design and further mechanism synthesis of the clamping and lifting mechanism.