Spatial light modulators (SLMs), extensively utilized in the optical field, offer substantial modulation flexibility and the capacity to generate complex wavefronts, necessitating precise wavefront sensing techniques. This study introduces a wavefront sensing technology for SLMs based on Hilbert phase-contrast imaging. This technology utilizes the Hilbert transform to introduce complex signal analysis into wavefront sensing, effectively preserving the high spatial frequency information and realizing the quantitative phase-contrast imaging with high accuracy. The experiments show that the spatial light modulator wavefront sensing technology based on Hilbert phase-contrast imaging can effectively detect the complex wavefront generated by the spatial light modulator. The average wavefront sensing error is less than 1% for 40 different phase regions, achieving a well phase contrast. The proposed technology is expected to be applied in research fields that depend on spatial light modulators, such as scattering imaging, holographic imaging, beam turning, laser shaping, and optical tweezers.