Provided is a breakage detection system and method for a scraper conveyor, wherein a speed measurement device of the detection system and a sprocket assembly of the scraper conveyor are coaxially installed. Encoders are installed on speed measurement gears of the speed measurement device. An output end of the speed measurement device is connected to an input end of a programmable logic controller (PLC). An output end of the PLC is electrically connected to an automatic alarm device and a digital display module. A power supply module is used for supplying power to the whole system.