Abstract: The chemical compositions, tensile, impact, thickness directional properties and microstructure of the B grade ship plates with thickness 50 mm and 20 mm specifications produced by two refining processes were compared, and whether they meet the requirements of the classification society were analyzed. The results show that the properties of the B grade ship plates produced by the two refining processes meet the requirements of the classification society. LATS refining process was selected when produced the B grade ship plates without thickness direction property requirements, and LF+RH refining process was selected when produced the B grade ship plates with thickness direction property requirements.