The main problems treated in this paper are as follows (1) Comparison of the measured value in NACA tank with the calculated by the author's, method. (2) A calculating method for characteristics of the submerged hydrofoil of a dihedral angle. In §2, the calculated lift and resistance are compared with the measured in NACA tank, from which it can be safely said that the accuracy of the calculating method proposed is reasonably good for the ordinary aspect ratio of the submerged hydrofoil In §3, a calculating method for characteristics of the submerged hydrofoil of a dihedral angle is proposed from the standpoint of the liftingline theory and wave resistance theory. Numerical calculations are made and it is shown that the numerical results are in good accordance with the American's empirical formula and Tinney's results. In §4, the characteristics of the submerged hydrofoil of vertical finite span are examined in connection with the ship rudder which can be obtained as a special case. In §5, the surface waves caused by the submerged hydrofoil of a dihedral angle are examined.