In many workplaces, we need to carry some heavy stuff along a fixed route, in order to reduce the workload of staff, this paper proposed a kind of small freight robot based on single chip microcomputer. In this design, we use AT89S52 chip as the main control chip, design the electromotor drive circuit use L298N chip. The robot is driven by gear motor, using black and white line sensor, infrared photoelectric switch and wireless transceiver etc. to achieve the following functions: automatic tracing, sound and light alarm, obstacles avoidance, remote control and so on. At the same time, the freight robot can carry about 100 kg weight and has the characteristics of low cost and easy to maintain. The design is suitable for the transportation of small amount of goods, such as a workshop, airport and quick distribution station. It is flexible and the transportation cost is low, so it has a broad application prospect.