Metal on metal (MoM) total hip arthroplasty was reintroduced since 1989 to face the problems of joint replacements of young active adults. 20 cases of MoM total hip replacements were done during the period of Jan. 2002 to April 2004 using with large- sized femoral heads prostheses of Cormet 2000. Specific parameters in choosing these implants were considered to reach, as much as possible, the optimal tribological conditions for MoM hip articulations. The mean age of the patients at time of operations was 48 years ( 34-64 years). The mean follow-up duration of the cases was 16 months. The average pre-operative Harris Hip scoring was 44 improved to 91 postoperatively. No serious post-operative complications were observed in this young age group during the period of follow-up. Longer period of follow-up is needed to establish a solid result