[Objective] To assess the effectiveness and safety of Shuanghuang Powder for hip synovitis in non-traumatic osteonecrsis of femoral head (NONFH). [Methods] 95 patients with 143 hips in non-traumatic osteonecrsis of femoral head were evaluated in this retrospective study. Volume of hip synovitis and Harris score were evaluated before and after treatment of Shuangbo powder. [Results] After treatment, the average volume of hip synovitis and Harris hip score were (4470.84 ± 3972.04) mm3 and (74.21 ± 14.29) respectively, which decreased significantly conpared with those before treatment (7937.06 ± 6225.62) mm3 and (74.21 ± 14.29) (P < 0.001). In subgroup analysis, for 9 hips in ARCO stage I, the average volume of hip synovitis after treatment with Shuangbo powder was (731.11 ± 331.64), which decreased significantly compared with that before treatment (776.67 ± 353.41) mm3 (P =0.011). For 52 hips in ARCO stage II, the average volume of hip synovitis after treatment with Shuangbo powder was (1323.85±995.33)mm3, which decreased significantly compared with that before treatment (1508.85±1011.69)mm3 (P <0.001). For 66 hips in ARCO stage III, the average volume of hip synovitis after treatment with Shuangbo powder was (6035.45±3597.71)mm3, which decreased significantly compared with that before treatment (10018.79±4544.65)mm3 (P <0.001). For 16 hips in ARCO stage IV, the average volume of hip synovitis after treatment with Shuangbo powder was (6410.62±744.73)mm3, which decreased without significance compared with that before treatment (8300.62±1092.40)mm3 (P >0.05). From ARCO stage I to IV, Harris scores before treatment with Shuangbo powder were (90.44±2.96), (86.04±2.58), (79.77±3.45), (54.06±5.36) respectively, which were increased significantly compared with baseline (87.33±2.78), (84.60±2.64), (72.55±5.76), (39.94±4.23) (P <0.05). No serious adverse effects were observed in all patients. [Conclusion] The treatment of hip synovitis with Shuangbo powder in NONFH is effective and safe, especially for patients with ARCO stage I ~ III.