A transmission controlling apparatus includes: a memory; a transmitting and receiving interface connected to a plurality of wireless stations each of which wirelessly transmits a signal; and a processor connected to the memory and to the transmitting and receiving interface. The processor executes a process including: calculating, for each of the wireless stations, an index indicating a magnitude of interference suffered by the signal wirelessly transmitted from the wireless station, the interference being caused by the signals wirelessly transmitted from one or more other wireless stations; determining a resource to be allocated to each of the plurality of wireless stations in accordance with the index calculated for each of the wireless stations; and transmitting transmission data to each of the plurality of wireless stations by using the determined resource.