A full wave numerical method is developed for fast wave current drive in tokamak plasmas,in which finite Larmor radius effects and parallel dispersion are taken into account.A physical model with full wave are developed.Electric field distribution in radial is obtained.It shows that fast wave can propagate to central plasma;Mode conversion happened near central plasmas;Fast wave can drive current in centre to improve balance current profile;Parallel electric is weaker than that in vertical direction.The current is droven by Landau damping and transit-time magnetic pumping.