A transport format determination apparatus and method determines, for each transport channel, transport formats to be used for supplying data every data-arrival-interval. A plurality of transport channels different in data-arrival-interval are free to be multiplexed with each other. A fault of data on the plurality of transport channels is detected. At least one first data-arrival-interval of at least one first transport channel is determined, based on a result of detecting fault of data on a second transport channel having a second data-arrival-interval shorter than the at least one first data-arrival-interval. A candidate of transport format combination indicators to be used for decoding post-received data and for isolating transfer blocks is restricted.