An experiment has been conducted to clarify the nature of ship motions and wave impact phenomena in bi-directional wave conditions. Irregular and regular waves traveling at a sharp angle have been generated simultaneously using two kinds of wave maker, one of which is capable of making snake motion to generate arbitrary waves in oblique direction. Discussions are made on the relationship between wave formations and the ship motions and the occurrence of slamming or green sea impact. It is concluded that bi-directional waves at a sharp angle could be dangerous if it encounters the ship in bow wave condition and that wave height distributions and motion amplitude distributions can be approximated by Quasi-Rayleigh distribution more appropriately than Rayleigh distribution in the bi-directional waves stated here.