A scraper conveyor tension chain device with a sweeping function comprises a transmission device, a steering sprocket, a scraper chain and ledges. A tension chain device is arranged above the scraper chain on the steering sprocket, a sweeping device is arranged on the tension chain device, the tension chain device comprises a crank slider mechanism and two sliding grooves, the two sliding grooves are symmetrically and fixedly formed in the ledges on two sides by inclination angles, a tension shaft is arranged between the two sliding grooves and mounted on bearing blocks through bearings, the middle of the tension shaft is provided with a tension sprocket matched with a transmission chain, the sweeping device comprises a tension shaft sleeve, and a plurality of groups of sweeping heads are arranged on the circumference of the tension shaft sleeve at intervals and fixed onto the tension shaft sleeve through springs. Sticky coal on a scraper is swept by scraping teeth on the sweeping heads, the problems of friction, chain jumping and jamming caused by the sticky coal on the scraper are solved, the scraper conveyor tension chain device is particularly applicable to a double center chain scraper conveyor, purely mechanically driven, simple in structure, convenient to mount and detach and reliable in running, and an original scraper conveyor is less modified.