In order to solve the problems that traditional veneer slicer has low automation degree，low sliced precision and low efficiency, the work designs the control system of sides continuous veneer slicer. The processing technology of slicing small-diameter wood for sides continuous veneer slicer was firstly analyzed, and then the control system design requirements were formulated. The control system resource demand statistics were completed and the electrical components were selected according to the control system demand and the working process of slicing small-diameter wood. The PLC control program and the interface of sides continuous veneer slicer were designed and the program and interface were introduced by taking a sliced veneer cycle as example. After the operation of the control system, the automation degree and precision of the sides continuous veneer slicer for small-diameter wood could be greatly improved, and the feed accuracy reached 0.026 mm. In conclusion, the control system of the sides continuous veneer slicer for small-diameter wood based on PLC can meet the requirements of improving the degree of veneer slicer’s automation and accuracy and has great economic benefit.