Provided are: a multiplexing apparatus for comparing priorities, selecting multiplexed data in an arbitrary output rate, and outputting the multiplexed data; and a receiving apparatus for combining data outputted from the multiplexing apparatus in a time sequential order, and thereafter outputting the data. A multiplexing apparatus (1) includes: a multiplexing buffer (2) that receives and temporarily stores encoded units to which respective priorities have been added; a multiplexing control unit (4) for sequentially selecting, based on the priorities and data amounts of the encoded units, encoded units each having respective data amounts which can be transmitted in a unit time and also having a higher priority than any other one; and a multiplexing unit (3) for sequentially selecting and multiplexing, under control of the multiplexing control part, encoded units, from among the encoded units stored in the multiplexing buffer, each of which has a respective data amount which can be transmitted in the unit time and also has a higher priority than any other one, and outputting the encoded units.