Abstract: A probe test apparatus comprising a test section for testing a wafer, a cassette having an opening at one side through which the wafer is taken into and out of the cassette, grooves formed in inner faces of both sides of the cassette to hold wafers therein, and a convex member projected downward from the underside of the cassette, a stage on which the cassette is mounted keeping the wafers therein substantially horizontal, and holder members projected upward from the top of the cassette-mounted stage and having a recess into which the convex member of the cassette falls, wherein when the convex member is not fitted into the recess but contacted with the holder members, the wafers in the cassette are tilted and when it is fitted into the recess, they can be kept substantially horizontal in the cassette to thereby position the cassette relative to the test section.