A ship environmental information detector, a route setting device, a method of detecting ship environmental information, and a program are provided, which are capable of more surely and accurately detecting environmental information in the vicinity of a ship. A ship environmental information detector 12 includes an ocean wave detecting module 14, a surface tidal current detecting module 15, and a controlling module 16. The ocean wave detecting module 14 is configured to detect an ocean wave in the vicinity of a ship 50. The surface tidal current detecting module 15 is configured to detect surface tidal currents 54 (541 and 542) in the vicinity of the ship 50. The controlling module 16 controls outputs of the detecting modules 14 and 15 based on the detection results of the detecting modules 14 and 15, respectively.
