The advantages and disadvantages of the existing structure of multi-channel fiber optic rotary joints are compared, a structure of axial magnetic driven multi-channel fiber optic rotary joints is proposed. In this structure, the paraxial optical signal is transmitted by optical coupling both optical fiber collimator of main rotational axis and optical fiber collimator of driven shaft, which relies on the magnetic driven structure and precision gear transmission mechanism. The continuous transmission of the center channel’s optical signal is implemented by the magnetic driven structure. The channels increase with increase of the axial size. This fiber optic rotary joint is simple and easy, avoiding the drawbacks of traditional structure, simplifies the process, reduces the cost.