The invention provides an air-ground cooperative communication method and apparatus based on non orthogonal multiple access. The method comprises the following steps: obtaining first channel information among a satellite and target users, and obtaining second channel information among a base station and the target users; scheduling and grouping the target users by using target channel information to obtain a scheduling and grouping result, wherein the scheduling and grouping result comprises satellite users and base station users, the base station users comprise at least one NOMA group; generating a wave beam by using the target channel information on the basis of the scheduling and grouping result to obtain a wave beam generation result, wherein the wave beam generation result comprises a satellite wave beam and the wave beam of each NOMA group; and allocating transmitting power to the satellite and the base station on the basis of the scheduling and grouping result and the wave beam generation result, so that the satellite and the base station transmit signals according to the allocated transmitting power. The technical problems of relatively poor network quality of service caused by the larger data transmission pressure and insufficient system service capacity when the number of users is increased are relieved.