Abstract: As typical anisotropic Gaussian random fields, fractional Brownian sheets have been intensively studied in recent years. In this talk, we study the regularity of local times of fractional Brownian sheets, including the existence, joint continuity and smoothness (in the Meyer-Watanabe sense) of the local times. As applications, we derive regularity results of their collision local times, intersection local times and self-intersection local times. The main tools applied in our derivation are sectorial local nondeterminism of fractional Brownian sheets, Fourier analysis and chaos expansion of the local times. This talk is based on joint works with A. Ayache, Z. Chen and Y. Xiao.