To prevent a collision accident with leisure boats or the like and an accident entwining a screw with fixed nets or the like by improving handleability and durability of a float used for a buoy, a guide buoy, and installation of a fixed net, and enhancing visibility of the float by applying self-luminous action not requiring electric wiring.

The wave activated power generation light emitting float incorporates a wave activated power generation mechanism 20 performing power generation operation by a relative movement of a first relative movement element F1 with a second relative movement element F2 in the inside of an outer shell 11 formed to be hollow having watertight structure made of aluminum alloy, and is constituted by mounting a light emitting element D1 to the outer shell 11. The first relative movement element F1 and the second relative movement element F2 are excited by floating movement of the outer shell 11 with wave power to relatively move respectively.