The invention provides a warning device for preventing electric shock in fishing along an overhead power supply line. The warning device comprises a mounting rack provided with warning characters, andfurther comprises a radar sensor switch fixedly arranged on the mounting rack and used for perceiving whether someone enters a warning area for preventing the electric shock in fishing, a warning flashlight and a night flashing light used for sending out warning light in the daytime and night respectively, a solar assembly for providing a working power supply, a broadcaster for sending out warning sound, a camera for transmitting video to a background, and a centralized control box for master control, wherein the centralized control box is internally provided with a lithium battery pack and acircuit board, the circuit board is provided with a power module, a CPU module and a relay module, the CPU module is electrically connected with the radar sensor switch, the relay module is electrically connected with the CPU module, and the broadcaster is electrically connected with the CPU module; and the warning flashlight, the night flashing light and the camera are all electrically connectedwith the relay module. The warning device can work for 24 hours in one day to effectively prevent electric shock accidents in fishing.