Potential energy surfaces for the first singlet and triplet excited states of methane have been studied using multireference configuration interaction (MRCI) and equation-of-motion coupled cluster (EOM-CCSD) abinitio molecular orbital calculations. The vertical excitation energies for the T-1(2) and T-3(2) states are computed to be 10.64-10.66 and 10.25-10.30 eV, respectively. Two minima are found on the first excited singlet surface, 1 (similar to C-3v) and 2 (C-2v), with adiabatic excitation energies of 9.16-9.25 and 8.39-8.52 eV, respectively. No minima is located on the triplet surface. Vibronic spectra, calculated based on the geometries, vibrational frequencies, and normal modes of the ground and excited states, reproduce well the experimental results. The spectra due to the 3s(C-2v)<--1t(2) transition start at similar to 8.63 eV and form a broad underlying continuum. The 3s(C-3v)<--1t(2) transition is shown to be responsible for the minor fine structure observed in the experimental absorption spectra between 9.5 and 10.6 eV. Dissociation pathways leading to various photofragmentation products are discussed on the basis of the calculated minimal energy pathways of H and H-2 elimination, Production of CH3((2)A(2)") and fast hydrogen atoms, the major channel observed experimentally, is speculated to occur either via the S-0<--S-1 internal conversion or, more likely, via the S-1((1)A")-->T-1((3)A’) intersystem crossing followed by fast dissociation in the triplet state. Spin-orbit coupling between S-1 and T-1 has been calculated to be about 45 cm(-1).