Based on the existing phase-only spatial light modulator (SLM), a computer generated phase-only rainbow holographic near-eye display is proposed and realized. It is pointed out that the calculation of the phase distribution of the object light on the holographic plane under the band-limited condition and the control of longitudinal dispersion by high-frequency blazed grating are the key elements to realize the phase-only rainbow holography. When calculating the phase-only rainbow hologram, the complex amplitude distribution of the object light on the holographic plane is obtained by using the angular spectrum diffraction algorithm under the band-limited condition, and the complex amplitude distribution is encoded as the phase distribution by the bidirectional error diffusion algorithm first. Then, the phase of high-frequency blazed grating corresponding to the reference light is encoded, and the computer generated phase-only rainbow hologram is obtained. Finally,a holographic near-eye color display system including a white light point source, a collimating lens, a spatial light modulator, a 4f filtering system and an eyepiece is designed and the phase rainbow holographic near-eye display effect is obtained by optical reconstruction, which proves the effectiveness of the proposed method.