PURPOSE: To produce a composite sheet having anisotropy continuously, by orienting magnetic filamentary articles in a sheet of a mixture comprising the filamentary articles and a matrix dope, conveyed in a magnetic field, in the thickness direction, followed by solidifying the matrix.

CONSTITUTION: A mixture of (A) the filamentary articles F consisting of a magnetic material, which are cut to a given length, and (B) the matrix M is made to flow from the nozzle 6 downward to orient the filamentary articles F in the thickness direction by the magnets 7 and 8, and the mixture sheet is solidified. Silicone, urethane resins, etc. may be cited as the matrix. Iron, nickel, cobalt, or an alloy consisting mainly of at least one type selected from the metals may be cited as the material of the fi lamentary articles, and preferably have both magnetic properties and electrical conductivity