Disclosed are a chain tension regulating device used for the tail of a scraper and use thereof, comprising a body (16) ,and a telescopic mechanism, a bearing block (17), a connecting rod and a locking mechanism arranged on the body (16). The telescopic mechanism, the bearing block (17) and the connecting rod are sequentially connected, the telescopic mechanism driving the bearing block (17) to move to regulate the chain tension and automatically locking or unlocking the connection rod at one side of the bearing block through the locking mechanism. The bearing block in the device is connected to a sprocket wheel shaft at the tail of the scraper, and the sprocket wheel shaft is drove to move by the movement of the bearing block, so as to regulate tightness of the chain on the sprocket wheel shaft. Therefore, the purpose of regulating the chain tension is achieved, and the scraper chain can works in a proper degree of tightness, thus providing a technical support for the safe operation of the scraper.