A space optical coupling apparatus, including M first couplers, a phase adjustment apparatus, N beam splitters, M second couplers, a coupling apparatus, and a controller. The first coupler receives a beam, and couples the beam to the phase adjustment apparatus. The phase adjustment apparatus includes M phase adjusters, N beam splitters, and N detectors. Each beam splitter is configured to split a received beam into two beams, one sent to a corresponding detector and the other sent to a corresponding phase adjuster. The second coupler receives output light from the coupling apparatus, and transmits the output light into the space. The coupling apparatus is configured to couple a beam onto a single-mode fiber. The controller is configured to control, based on the beam intensity detected by the detector and the beam intensity on the single-mode fiber, the M phase adjusters to adjust the phases of the received beams.