The present piping modeling method requires detailed inputs from a designer to generate a piping model, and thus it takes much time for the designer to perform such task. Moreover, the piping model has no relation with that of hull structure. Thus, it is time-consuming and requires much effort if design changes arise. In this study, a method that generates quickly many pipes using a pipe tray and a conversion method that converts automatically the pipes into objects related with the hull structure are proposed. A piping modeling system based on the proposed methods is developed. The applicability of the developed system is demonstrated by applying it to the generation of the piping model of a deadweight 300,000ton VLCC(Very Large Crude oil Carrier). The results show that the developed system can quickly generate the piping model in relation with the hull structure.