The calculated results show that the performance of the ferrofluid-lubricated plane sliders is different obviously from the performance of plane sliders lubricated with Newtonian fluid or Bingham plastic. The yield stress causes the attached cores and increases the load carrying capacity of plane slider. In the case of a low velocity lubrication, the high applied magnetic field strength is of benefit to the load carrying capacity, since it can increase viscosity of a ferrofluid and can cause the attached cores in the lubricating film. When the adhered cores occur, the magnitude of optimum film thickness ratio of a plane slider lubricated with ferrofluid is much larger than 2.2 and increases with increasing applied magnetic field strength. In the case of a high speed lubrication, it is possible that no adhered cores appear and the film thickness ratio of 2.2 is advisable to reach a maximum load carrying capacity. The friction coefficient of a ferrofluid-lubricated plane slider is larger under the condition of a high magnetic field strength and a high shear rate.