This paper elaborates the impact characteristics of double hull structures in various ship types including bulk carrier, container ship, LNG carrier and oil tanker. Their own structural configurations, such as the strengthened topside tank in the container ship, affect the crashworthiness of double hull structures in ship collisions. Two striking bows are modeled so as to evaluate the crashworthiness of the double hull structures. The calculations are performed using LS-DYNA to assess the impact characteristics of four struck ships. The ship collision analysis also discusses the assumption of rigid bow in conventional analysis and its effect on the evaluation of side structural crashworthiness. The numerical force-displacement responses and absorbed energy-displacement curves of various ships are compared. The comparison aims to reveal the discrepancy of the crashworthiness of the four typical double hull structures. It is of importance to analyze their structural characteristics for the design of crashworthy structures.