Abstract: In order to assemble micro-parts and to obtain high efficiency for the microassmebly and to avoid complex camera calibration,an image Jacobian matrix online identification model based on BROYDEN is presented.We employ Chebyshev polynomial as a cost function of image Jacobian matrix identification to approximate the optimal value so as to satisfy the requirements for fast convergence of online identification.With identificated image Jacobian matrix,we design a proportional and differential(PD) controller,which meets the requirements for rapidness and smoothness of the system.In the microscope vision environment,we complete the visual servo task that micro-manipulator is positioned automatically and grips 3-D micro-parts under different magnification lens.The experimental results show that the proposed method obtains better robustness and satisfactory performance,reaching the system application requirements.