The results of cementless total hip arthroplasties in patients with osteonecrosis have been inferior to those in patients with other diagnoses. Fifty-eight primary total hip arthroplasties with insertion of a femoral stem with a circumferentially proximal porous coating and a cementless acetabular component were followed for a mean of 11.1 years. Fifty-seven (98%) of 58 stems were biologically stable, and one stem was loose. There were acetabular revisions in 18 hips (31%) because of polyethylene wear and osteolysis. One hip (1.7%) underwent revision of both acetabular and femoral components. Osteolysis around the acetabular component was seen on radiographs in 22 hips (37.9%). Femoral osteolysis was seen in 9 hips (15.5%), and there was no osteolysis below the lesser trochanter in any hip. Second-generation femoral prostheses provide excellent fixation in patients with osteonecrosis of the femoral head. However, a high rate of polyethylene wear and osteolysis in these high-risk patients remains a challenging problem.