The potential energy surface for the reaction of CH3 with C5H5 has been investigated using the ab initio G2M (ree, MP2) and B3LYP/6-311G(d,p) methods. The most favorable channel is the elimination of the hydrogen atom from the ring carbon of the C5H5CH3 intermediate, C5H5+CH3→C5H5CH3→C5H4CH3+H. Neither step has a barrier, and the overall reaction endothermicity is 7.2 kcal/mol. The calculated strengths of the out-of-ring C-C bond in C5H5CH3 and the C-H bond in C5H6 are 72.5 and 83.4 kcal/mol, respectively. The C-H bond in C5H6 is predicted to be significantly stronger than the previous experimental estimates. The elimination of H from the methyl group of C5H5CH3 requires an activation energy by 22.9 kcal/mol higher than the elimination of H from the ring carbon. Subsequent hydrogen elimination in the C5H4CH3 and C5H5CH2 leads to the formation of fulvene. Fulvene can also be formed directly from C5H5CH3 by the 1,2-H2 elimination or by the 1,1-H2 elimination, followed by the 1,2-H shift. However, these channels cannot compete with the splitting of the hydrogen atom because of high barriers. In addition to these unimolecular processes, C5H5CH3 can be converted to fulvene by bimolecular reactions with atoms or radicals. Fulvene can isomerize to benzene under high-temperature combustion conditions, making C5H5+CH3 a potential source of aromatics.