It is an object of present invention to provide an efficient method for grinding of the surface of a work and an apparatus thereof, using a magnetic fluid containing abrasive grains.The method of the present invention for grinding a work immersed in a magnetic fluid containing abrasive grains filled in a container, said magnetic fluid being given a magnetic field from the outside of the container with magnet comprises: immersing a floating pad in said magnetic fluid at a position adjacent to the work, said floating pad being given a buoyant force by said magnetic field whereby the abrasive grains existing between the floating pad and the work are pushed onto the work and giving a mutual motion between the work and the magnetic fluid containing abrasive grains.In conventional method for grindings using a magnetic fluid containing abrasive grains and without the floating pad, the grinding load has been mainly dependent upon the buoyant force of abrasive grains, but the grinding rate thereby was too small owing to rather little buoyant force of abrasive grains.According to the present invention using the floating pad, the grinding rate is significantly improved by strongly pushing abrasive grains onto the surface of the work, resulting from larger grinding load and the resistant power of the floating pad to the grinding direction.