Leafy vegetable harvesting machines are made with the aim of improving the efficiency of harvesting, reducing the damage to the plant, reducing the need for manpower and also reducing contamination. In current research, a cutting system for leafy vegetable harvesting machine was designed and constructed. The system was tested on watercress, spinach and basil. The machine consists of a band saw blade that is placed on two pulleys. The pulleys are rotated by an electric motor powered by three-phase electricity. Driving pulley was connected to the motor by a shaft and a coupling. Two ball bearing were used to prevent angular deflection of the shaft. The driven pulley is also attached to the U-shaped frame by a shaft and ball bearing. The bearing connected to the movable pulley is responsible for adjusting the required tension of the saw blade. A screw and two nuts were used to provide the blade tension by screwing. The assembly is mounted on an inverted U-shaped metal frame, which is attached to the main chassis of the machine. The wheels are connected to the main chassis by a height adjustment mechanism. The constructed system was tested at blade linear velocities of 3.7T 5 and 6.3 m/s and forward speed levels of 1, 1.5 and 2 km/h. Experiments were designed by Minitab 2018 software and 13 experiments were designed for each of the three plants using the central composite design method. According to the results obtained in this study, the optimal blade linear velocity was 6.3 m/s and the forward speed in the range of 1.7 to 2 km/h. Also, the stems were cut by this machine without crushing and caused the least damage to the plants.