Provided is an autonomous ship navigation apparatus including an acquisition unit configured to acquire a surrounding environment image, marine information, and navigation information, a map generation unit configured to generate a grid map by displaying topography, a host ship, and an obstacle corresponding to the marine information and the navigation information in the surrounding environment image, and a sailing method determination unit configured to determine a sailing method of a ship through deep reinforcement learning based on the grid map, the marine information, and the navigation information.