A reduced chemical mechanism for primary reference fuels (PRFs) and their mixtures has been developed to investigate the homogeneous charge combustion ignition (HCCI) combustion and emissions (uHC, CO, and NOx) processes. The reduced mechanism involves 42 species undergoing 62 reactions and has been validated against experiments under engine relevant conditions. First, the ignition delay time predicted by the reduced mechanism has been compared with shock tube experiments, and good agreement has been obtained for the PRF100, PRF90, PRF80, PRF60, and PRF0 fuels over the temperature range 667-1250 K at stoichiometric conditions. Second, the ignition delay time and burn rate has been validated against a rapid compression machine over the equivalence ratio range 0.2-0.5 and the initial temperature range 305-341 K for PRF90 fuel. Third, the ignition delay times and NOx emissions have been compared with HCCI engine experiments and good agreement has been obtained for the PRF90, PRF75, PRF50, and PRF25 fuels.