In multifrequency heterodyne-structured light three-dimensional measurement technology, phase errors significantly affect the measurement accuracy. Hence, this paper proposes a phase-error correction method based on multifrequency heterodyne. First, a nonlinear correction was performed on the projection device using a polynomial to deduce the relationship between the intensities of the output and input lights. Subsequently, this polynomial was used to correct the input phase-shifted fringe pattern. A Gaussian adaptive bilateral filtering algorithm was proposed for denoising the phase-shifted fringe pattern captured by the camera, and the processed images were used to generate a truncated phase using the phase-shifting method. Absolute phase recovery was performed by optimizing the forward construction of the continuous auxiliary phase and the inverse derivation of the truncated phase-series constraint process. Experimental results show that, after correction, the nonlinear average absolute error and root mean square error were reduced by 74.58% and 77.65%, respectively, thereby effectively reducing the nonlinear error of the absolute phase. Additionally, the proposed method effectively suppressed the phase-jump error, thus resulting in a smoother surface for the point-cloud model. When measuring the step height difference of the standard block, the absolute error and relative error were reduced to 0.034 mm and 0.38%, respectively, thus enhancing the measurement accuracy and robustness of the structured light three-dimensional measurement system.