Non-rigid image registration algorithm based on viscous fluid model is an appropriate method for registering objects with large difference.The critical part of the model is the viscous fluid kinematical partial differential equations（PDEs)

which are very time-consuming to be solved by direct discretization combined with successive over-relaxation method(SOR).In order to reduce the time cost

a fast method based on viscous fluid B-spline model is developed.Firstly

B-spline is used to model the vector fields in the PDEs

changing the unknowns to the coefficients of B-spline.Secondly

by using of fast Fourier Transform(FFT) and some special attributes of B-spline

formulas of directly calculating the coefficients are deduced.Experimental results show that new method is a fast non-rigid registration method without precision loss.