Abstract: This paper introduces the design of inter-satellite optical communication links by use of orbital-angular-momentum(OAM) as a new multiplexing dimension. In theory, the OAM has infinite number of modes and each mode is orthogonal to each other, which means that the communication system based on OAM multiplexing can greatly improve the spectral efficiency and channel capacity. This paper also introduces the conceptual diagram of the transmitter and receiver for the inter-satellite optical link. The transmitter uses a non-diffracting Bessel-Gaussian optical beams for coding, modulation and OAM multiplexing, and the receiver removes the azimuth phase of the OAM beams with a spiral phase opposite to the transmitter to recover the plane phase wavefront of the beams and recovers the date through a photodetector, a demodulator, and a decoder. In addition, the influence of Doppler frequency, satellite swing and background noise on the system is also described. The proposed scheme of inter-satellite optical communication links based on OAM technology is of great significance for the design and implementation of future high-capacity inter-satellite communication systems.