We have developed three types of muldexes; they are 140Mbit/s muldex, 565Mbit/s muldex and monitor & control muldex for a 565Mbit/s optical fiber transmission system. The frame format of our own type has been constructed for the M&C muldex, and new direct and parallel reframe techniques have been invented for 140Mbit/s, and 565Mbit/s muldex. Their functions, configurations and perform ance evaluations are described here.