High-resolution angle-resolved photoelectron spectroscopy (ARPES) has been performed to investigate valence-band photoemission in C60 single crystals, which were cleaved in ultra-high-vacuum systems. The results present angle-dependent modulations in intensities of valence-band photoemission of the C60 single crystal. The observed intensity modulations are caused by polarization influence and photoelectron diffraction (PED) effects, of which the latter is also responsible for the similar oscillations produced by varying incident photon energies. The calculated results indicate that only photoelectrons scattered by the top hemisphere of C60 molecules dominate the angle-dependent interference modulations.