We report results of ab initio calculations on the main features of the potential energy hypersurface of fluorooxirane H2COCHF near the equilibrium geometry and for several possible reaction pathways in thermal, chemical activation, and infrared laser chemical experiments. The ab initio results are compared to recent spectroscopic and kinetic data for this compound. The laser chemical reaction dynamics during and after infrared multiphoton excitation is simulated in detail ab initio and with adjustment of some of the potential parameters to reproduce the experimentally dominant channels leading to ketene and HF (or DF) for various isotopomers.