The process of capturing wave energy by a round-shaped island with a conical relief for the surrounding bottom is studied in this work. The kinematics of the tsunami wave having initially straight front near such an island was investigated by the method of step-by-step orthogonal advancement of wave front. An estimate was obtained for a part of wave energy that refracted and captured by the bottom slope surrounding the island. Numerical modeling of the same problem was also carried out within the framework of the shallow-water model; this modeling con- firmed the results obtained by the kinematic method. The quantitative assessment of the part of wave energy reflected by the island and captured by its conical shelf is in good agreement with the results obtained by kinematical method.