The traditional Poisson surface reconstruction algorithm often generates pseudo-closed surfaces along the internal and external edges, resulting in a deviation of the reconstruction results. To address this issue, an improved method based on boundary region growth is proposed. First, based on the Poisson surface, the object boundary points are extracted by normal lines and the continuous boundary curves are fitted. Then, vector cross multiplication is utilized to screen the neighboring points of the boundary and extract the boundary features. Finally, a double-ray method is employed to extract initial seed points for the boundary inner surface, and the Poisson surface is segmented using the region growth method, which is constrained by the boundary characteristics. Experimental results show that the proposed method can effectively eliminate pseudo-closed surfaces in the model and enhance the accuracy and integrity of reconstructed surfaces. This method has good adaptability and performance stability with different types of objects.