In order to study the dynamic characteristics of the eccentric non-circular gears & crank-rocker weft insertion mechanism, dynamic models of the mechanism were established. The dynamic characteristics were analyzed by using the stepwise solving solution of dynamics equations sets. The tooth contact force as well as the force at each hinge point were calculated by means of dynamic analytical software which is complied based on Visual Basic 6.0. The calculation results provided the theoretical bases to design and optimize the dynamics parameters and the strength analysis of the device.