Abstract: In this paper,we studied a one-dimensional plasma current sheet by means of the regular pattern of motion of charged particles moving in a neutral sheettmagnetic field.Aguiding centre theorem similar to that of Alfven's was used,the "8" shaped motion in non-perturbation region (where the magnetic field is small or equal to zero) is divided into two "circular" motions.Bach circular motion is equivalent to a magnet.So the "8" shaped motion is equivalent to two magnets in opposite directions.The electric current of plasma is derived from j=en+c(这里有图片19820103-21-1.GIF)×M where the distribution function of plasma is a function of constant motion.We found that the current sheet is mainly due to the "inverse drift" motion in the non-perturbation region.We have also studied the relation between charged particle motions and the magnetic field,and derived a self-consistent magnetic field.