The purpose of this study is to provide estimations of steel weight for new ships in the early design stages. Principal Component Analysis (PCA) is applied to estimate the steel weight for the whole ship as well as its segments. The database is based on three-dimensional (3D) computer aided design (CAD) systems. In order to obtain more precise estimation, Multiple Retrieval Case-Based Reasoning (CBR) is used to find the fitting historical data for the individual configuration segments of the target ship. In comparing estimation variability, the maximum error for the whole ship estimation is about 5%; the error of the configuration segments estimation is 3.74%, clearly less than the whole ship estimation; hence, the configuration segments estimation is able to obtain accurate steel weight.