A test apparatus including an optical coupler for optically coupling a main frame and a test head is provided. The optical coupler has a plurality of optical fiber cables, a cable storage chain for bundling a stored portion except for a non-stored portion in a part of the test head side and a non-stored portion in a part of the main frame side of the plurality of optical fiber cables and storing the same, a test head side cable storage unit provided at the boundary between the non-stored portion and the stored portion of the plurality of optical fiber cables on the test head side and being capable of adjusting a length for storing therein the non-stored portion on the test head side and a main frame side cable storage unit provided at the boundary between the non-stored portion and the stored portion of the plurality of optical fiber cables on the main frame side and being capable of adjusting a length for storing therein the non-stored portion on the main frame side.