[Objective] To retrospectively study and discuss the indications,surgical techniques and effect of treating hallux valgus with modified Austin operation-Chevron-Gerbert osteotomy or Chevron-Youngswick osteotomy.[Method]From October 1998 to April 2006,34 patients(62 feet)with hallux valgus were treated with modified Austin operation.The X-ray films of all patients were collected preoperatively,two weeks postoperatively and during the follow-up.The hallux valgus angle(HVA),intermetataral angle(IMA),proximal articular set angle(PASA)and distal articular set angle(DASA)were measured and analyzed on radiogram.[Result]All patients were followed up for 1-8 years(mean 3.6 years).HVA before and after surgery was 33.50??1.02?and 13.6??0.826 respectively.IMA was 16.0??0.837?before and 8.6??1.078 after surgery.AOFAS score was 44.8?5.7 before,and 87.6 4.2 after surgery.Significant difference was found between the results.According to AOFAS rating system,46 feets had a excellent result and 10 feet had a good result and the other 5 feet had a fair result.The rate of excellent or good results was 90.3%.[Conclusion]The modified Austin operation is a good,simple and reliable operation means for treatment of hallux valgus,which especially applies to severe hallux valgus with big PASA.The adductor hallucis or the sesamoid is not necessarily interfered in patients with slight or moderate hallux valgus.