Abstract: A method of data association(DA) and data fusion (DF) in multisensor multitarget tracking (MSMT) is discussed. First, data association in single sensor is rea lized by increasing measuring elements. Second, integer programming is applied to realize scanning association, which is also extended to route association. Finally, a fusion method to represent trajectory parameter with spline function is used, which solve the problem of huge computational cost. This simple method has higher correct association percent and smaller computational cost, and also utilize the measuring information fully.