The residual state means ultimate steady shear state after large deformation. The ring shear apparatus is considered to be the most suitable apparatus for forming this state in soils. However, a standard of ring shear tests has not been established, because shear deformation to reach the residual state is not clear; also, it is very difficult to measure pore water pressure in soils during shearing. First of all, the effectiveness of constant volume tests in ring shear tests was demonstrated in this study. Then, the residual state was not verified based on measuring pore water pressure but based on stress path obtained from constant volume tests. Finally, effective and simple methods to measure the residual strength were proposed.