This study investigated the effect of bone mineral density (BMD) on the diffusion coefficient (DC) of bone cement in percutaneous vertebroplasty (PVP) and the correlation between the DC and the efficacy after PVP. This was a retrospective study of PVP cases with follow-up longer than 12 months. The cases were assigned to 3 groups according to the BMD: BMD decrease group, osteoporosis group, and severe osteoporosis group. The 3 groups were compared regarding bone cement injection volume (IV), diffusion volume (DV), DC, visual analog scale (VAS) score, Oswestry Disability Index (ODI) score, and vertebral height loss ratio (VHLR). The correlation between DC and BMD, IV, DV, and VHLR was analyzed. The least significant difference test was used for comparison among the 3 groups, and the Pearson correlation coefficient was used for correlation analysis. There were a total of 132 cases, including 34 males and 98 females with a mean age of 76.5±9.6 years. The DV was larger than the IV in each group (P<.05). There was no statistically significant difference in the IV, VAS score, and ODI among the 3 groups (P>.05). However, there were significant differences in the DC and VHLR among the 3 groups (P<.05). Correlation analysis showed that there were significant correlations between BMD and IV (-0.716), BMD and DC (0.754), IV and DV (0.502), and IV and DC (-0.666) (P<.01). Scatter plot showed that the correlation between IV and BMD was r=0.716, R2=0.513, and the correlation between DC and BMD was r=0.754, R2=0.568. The DV was larger than the IV in PVP, and BMD was closely related to the DC. The higher the BMD, the higher the DC. Short-term follow-up revealed that the DC was inversely proportional to the VHLR. [Orthopedics. 2021;44(x):xx-xx.].