Disclosed are a method and apparatus for processing source data of a synthetic aperture radar in a satellite, including receiving source data generated based on a signal returned after an electronic device steers a beam from a synthetic aperture radar and backscatters, setting a plurality of subswaths after the electronic device parses the source data, storing based on the plurality of subswaths after the electronic device decodes the source data; and generating image data after the electronic device calls the decoded source data in the order of the plurality of subswaths.