In order to explore the influence of particle shape on the mechanical properties of sand, three kinds of sand with different particle shapes, glass bead, quartz sand and glass slag were selected as the research objects. Firstly, the three-dimensional structure of three types of sand was reconstructed through CT scanning. The mean of three characteristic particle shape parameters, namely elongation (EI), flatness (FI), and sphericity (S) was selected as the overall regularity (OR) of sand particles. Statistical analysis was conducted to determine the feasibility of evaluating the shape of sand particles using the overall regularity OR. Then, the mechanical strength parameters of sand with 7 different overall regularity were obtained by conventional triaxial comprehension test, and the influence of sand particle shape on its mechanical strength was studied. The results show that the stress-strain curves of 7 kinds of sand are strain softening type, showing the characteristics of first shear shrinkage and then dilatancy. The overall regularity OR can reflect the mechanical characteristics of sand well, that is, with the decrease of the overall regularity OR, the strain softening becomes less obvious, but the peak-state deviatoric stress increases. The angle of internal friction of sand increases linearly with the decrease of the overall regularity OR, the apparent cohesion increases sharply, but the maximum dilatancy angle decreases with the decrease of OR. In addition, a good linear relationship between the critical internal friction angle and the overall regularity OR was obtained by linear fitting.