Background: To investigate the treatment effect of minimally invasive treatment of early osteonecrosis of femoral head (ONFH) with hydroxyapatite coated hollow titanium rod. Methods: From 1, January 2003 to 1, January 2019, 72 patients with ONFHⅡ Stage were selected. There were 50 males and 20 females, aged from 28 to 56. Onset time was 8~28 months. Lesion site: 18 left, 38 right, 16 bilateral. Causes of ONFH: 30 alcohol, 28 hormone, 9 trauma and 5 idiopathic patients. ARCO stage: 14 IIA, 33 IIB, 25 IIC. All patients underwent arthroscopic assisted minimally invasive percutaneous core decompression and bone grafting with hydroxyapatite coated titanium rod surgery. Visua Analogue Scales (VAS), Harris score and Images were used for assessing pain, hip joint function and the stability, respectively. Hip replacement was performed finally. Results: 16 patients with heavy hormone use history and femoral head collapse underwent Total Hip Resurfacing Arthroplasty (THRA) at the last follow-up. 24 months later, 8 ⅡB cases progressed to ⅡC, 2 cases were stable at ⅡC, 6 cases increased to Ⅲ, and underwent THRA. 12ⅡC cases progressed to Ⅲ, 2 cases were stable at Ⅲ, and 10 cases had articular cartilage surface collapse. THRA was administered 30 months after surgery. VAS score of individual patients increased and Harris score decreased 24 months after surgery, but there was no significant difference between the scores of 12 months and 24 months. The clinical effect of the last follow-up showed that the postoperative improvement rate of this group was 76.13%, among which the best was 100% in IIA, 79.48% in IIB, and the lowest was 58.06 in IIC. Both the patients with IIB or IIC, cases with aggravation and without change were hormonal ONFH. Conclusion: The treatment of ONFH with hydroxyapatite coated hollow titanium rod supporting the femoral head to prevent collapse is feasible. In addition to the Glucocorticoid-induced ONFH stage ⅡC outside, this method to other Ⅱ period lesions in improving the curative effect and preventing the collapse of femoral head articular surface is good and safe.