Abstract: The latest progress in theoretically and experimentally solving the major technical problems existing in applications of magnetic fluid seal:including, but not limited to the sealing of a large gap, sealing of a large diameter shaft, sealing of a shaft rotating at a high speed and sealing of a fluid medium, was tentatively reviewed.The discussions focused on:i) the technical advantages of the magnetic fluid sealing over the conventional sealing; ii) the proposed possible solutions of the above mentioned application problems with specific examples reported in literature; and (iii) the development trends of magnetic fluid seal.In addition, the hot-spot research issues of basic and technological interest in development of magnetic fluid seal were also discussed in a thought-provoking way.