Abstract: In order to increase the number of orbital angular momentum(OAM) modes transmitted by a ring photonic crystal fiber and to optimize the mode dispersion and confinement loss during fiber transmission, a dual-conducting-mode ring photonic crystal fiber with near-zero flat dispersion and low confinement loss was designed in this paper. The fiber consisted of a six-layer refractive index ring auxiliary structure to isolate the inner and outer mode-conducting regions, and the outer cladding region was provided with three layers of air holes with gradually increasing radii. The finite element method was used to analyze the mode dispersion and confinement loss of the fiber by varying the refractive index and thickness of the high refractive index rings, the spacing of the air holes, and the radius of the air holes to determine the optimal structure. The results show that under the optical structure, in 1.5 μm~1.7 μm the dual-conducting-mode ring photonic crystal fiber can transmit 286+126 OAM modes, and the effective refractive index differences are all greater than 2.81×10⁻⁴ in both the inner and outer guiding-mode regions, the mode dispersion is in −3 ps/(nm·km)~3 ps/(nm·km), and the mode confinement loss is in 2×10⁻⁹ dB/m~8×10⁻⁸ dB/m. This study provides a theoretical reference for enhancing the communication capacity and communication efficiency of photonic crystal fiber.