The present invention relates to the field of communication transmission, and in particular, discloses an optical channel data unit service transmission apparatus and method. The switching apparatus includes a first ODU service processing unit, a timeslot allocating unit, a switching output port allocating unit, an Ethernet switching unit, and a second ODU service processing unit, and forwards an ODU service according to a timeslot mapping table and a frame period timeslot table corresponding to the ODU service.