A reduced mechanism, which could couple with a multi-dimensional computational fluid dynamics code, was developed for the chemical kinetics of diesel surrogate fuel oxidation in modeling polycyclic aromatic hydrocarbon (PAR) formation under homogeneous charge compression ignition (HCCI) diesel engine conditions. The complete kinetic mechanism, which comprised 697 reactions and 153 species, was reduced to a minor mechanism that included only 141 reactions and 75 species using the sensitivity and reaction path analyses. Validation of the present mechanism was also performed with experiments from the shock tube available in the literature, and good agreement between modeling results of the detailed mechanism in the shock tube and HCCI engine was obtained. The results showed that this reduced mechanism gave reliable performance for HCCI combustion predictions. Numerical results also displayed that those PAH concentrations decreased with the increase of the inlet air temperature and equivalence ratio.