When measuring the front surfaces of transparent objects by using phase measuring deflectometry (PMD), the reflections from the front and back surfaces of the object are superimposed, resulting in parasitic reflection, which makes it difficult to accurately reconstruct the front surface of objects. In this paper, we proposed a front-surface PMD method that suppresses parasitic reflections of transparent objects. Firstly, the initial phase of the front surface was extracted by continuous wavelet transform. Then, an optimized model was constructed by combining the multi-frequency phase-shifting method to obtain the accurate phase. Finally, the gradient integral was used to restore the three-dimensional (3D) morphology of the transparent object surface. The surfaces of transparent glasses and plano-convex lenses were measured using the above theory. Compared with the multi-frequency phase-shifting method, the reconstruction error of the 3 mm glass plate decreased from 21.81 μm to 15.72 μm, the error of the 4 mm glass plate is reduced from 19.98 μm to 13.46 μm, and the radius of curvature error of the plano-convex lens is reduced from 39.44 μm to 16.59 μm, thereby improving the accuracy of the front surface of transparent objects measurements.