Objective To calculate the volume of maxillary sinus and sphenoid sinus of adults in China by CT, and to analyze the differences of gender in the adult maxillary sinus and sphenoid sinus.  Methods Ninety-three CT images of sinus were randomly selected from Peking University Third Hospital. The digital model of maxillary sinus and sphenoid sinus was reconstructed by Mimics17.0 3D reconstruction software. And the sinus volume was obtained by the three-dimensional digital model.  Results The average volume of the right maxillary sinus in the male was (16.69±6.90) ml, and the average volume of the maxillary sinus in the left side of the male was (16.88±7.12) ml. The average volume of the right sphenoid sinus of male was (4.62±2.99) ml, and the average volume of the left sphenoid sinus of male was (5.58±3.72) ml. The average volume of the right maxillary sinus in female was (11.39±5.63) ml, and the average volume of the left maxillary sinus in female was (11.37±5.38) ml. The average volume of the right sphenoid sinus of female was (4.12±2.53) ml, and the average volume of the left sphenoid sinus of female was (3.32±2.30) ml. The left sphenoid sinus and bilateral maxillary sinus volume had gender differences.  Conclusion Three-dimensional reconstruction can quickly obtain a three-dimensional model of the sinus, accurately calculate the sinus volume, and indirectly reflect gender through the sinus volume. It provides a certain reference for further understanding of sinus anatomy.