This paper presents determination of detonation pressure history in Trimonite 2 and pressure history in unsymmetrical collision of metal plates under the action of a slipping detonation using a manganin pressure gauge. In the experiment，it is found that initial part of detonation pressure history is a sharp pulse of short duration and the sharp pulse is direct1y followed by a pulse of longer duration which is approximate to rectangle，and the pressure history in collision of plates has two apparent steps.