PURPOSE: To enable the transfer of two or more wafers arranged at an equal pitch to container different in equal pitch in one lot by a method wherein wafer chucks are made to be continuously variable in equal pitch.

CONSTITUTION: Two or more wafer chucks A, B,... are fitted to a vertical guide rod G in such a manner that they are slidable in a vertical direction as being kept horizontal in position, and a chuck section 11 and an arm 12 extending behind the chuck section 11 are provided in an integral structure. The chucks A, B,... can be made to vary in pitch by the change of the angle θof inclination of a chuck drive lever 13 which is able to pivot about a supporting point as a center in a vertical plane. When two or more wafers 6 housed in a cassette 5 are transferred to a port 7 different in equal pitch, the pitch of two or more wafer chucks 3 is previously set coincident with the wafer housing pitch of the cassette 5 and the wafer chucks 3 is made to move in both a horizontal and a vertical direction, whereby the wafer chucks 3 are made to confront the wafers 6 inside the cassette 5.