Diamond is a promising candidate for power electronics as well as for radiation detection1. In both cases, device optimization requires an accurate knowledge of electron and hole mobilities. In this study, time-of-flight (TOF) experiments were performed on intrinsic CVD diamond crystals to determine carrier mobilities. Electron-hole pairs were generated in a biased diamond layer by a rays. The resulting current peak was amplified and measured. The distribution of electron-hole pairs in the sample has also been studied by means of simulation with SRIM and Geant4. This distribution has then been used to simulate the charge transport in the diamond. A drift-diffusion model, coupled with Poisson’s equation, was implemented in COMSOL. These simulation tools have been used to optimize the sample and experimental setup geometry.