Aiming at the problem of low shelling rate and high seed-breaking rate of the impact shelling device for Camellia oleifera fruit, a shell-breaking device was designed, which consists of a shelling component, a feeding device, power and driving device, and a frame. The shelling component mainly comprises an outer casing, a rotor and an impeller, which are coaxially mounted to form a broken shell cavity. The Camellia oleifera fruit were accelerated by the rotor and the impeller rotating with high speed and broken by impacting with the rotor, the outer shell and the inner wall. In the working process, sufficient impact force is ensured to increase the shelling rate, and the arc-shaped guide plate is used to effectively reduce the seed-breaking rate. Take the moisture content of Camellia oleifera fruit, the spindle speed and the installation angle of the guide plate as the influencing factors. The shelling rate and seed-breaking rate were used as evaluation indicators to obtain the best combination parameters. The test results showed that when the water content of the Camellia oleifera fruit is about 60%, the spindle speed is 425 r/min, and the guide plate installation angle is 75°, the shelling rate was up to 95.37% with the lowest seed-breaking rate of 4.27%.