Abstract: Lightweight automobile is one of important issues of auto industry development. Aimed at lightening of brake disc, the friction behavior of SiC particle reinforced aluminum matrix composite against commercial friction material under dry sliding friction was studied and the friction mechanism was discussed. Results show that the friction coefficient increased with the increase of SiC content from 50% to 55% and enhanced normal load. The friction coefficient first increased with increase of sliding speed and then decreased. The friction temperature rise induced Al alloy softening and reinforcing particle shedding and thus transition of wear mechanism from abrasive wear to adhesive wear, which had obvious influence on the stability of friction coefficient.