It has been proved that extracorporeal shock wave therapy (ESWT) could promote new bone formation. Therefore, we designed an experiment to test the efficiency of ESWT on BMD in postmenopausal osteoporotic patients. The results showed that ESWT could effectively improve the local bone mass of the treated bone area within a short duration. Introduction This study evaluated the short-term effectiveness of extracorporeal shock wave therapy (ESWT) on bone mineral density (BMD). Methods A total of 64 postmenopausal osteoporotic patients were recruited and randomized into 3 groups in 2015. Groups A (n = 20) and B (n = 21) patients received a single-session of low- or high-energy flux density (EFD) ESWT in the left hip, respectively, whereas group C (n = 23) patients served as controls without the ESWT treatment. All patients self-administered alendronate sodium tablets orally for a year. The BMD of the lumbar spine (L2-L4), femoral neck, great tuberosity, and total left hip was measured before ESWT treatment and at 3, 6, and 12 months using dual energy X-ray absorptiometry (DEXA). Results At 12 months, the lumbar spine, femoral neck, great tuberosity, and total left hip BMD in all patients had increased (p < 0.01). The increase in lumbar spine BMD in group A patients was higher than that in group B patients (p = 0.03); other between-group differences were not observed (p = 0.73, group A vs. C; p = 0.06, group B vs. C). The femoral neck, great tuberosity, and total left hip BMD increases in group B patients were higher than that in either group A or C (p < 0.01, group B vs. A; p < 0.01, group A vs. C). Conclusion This study showed that ESWT could efficiently improve the local BMD; relatively, the high dosage was effective.