The invention discloses a precise weighing and automatic sorting production process. The process comprises the steps that A, products are placed on a cleaning station to be cleaned; b, after being cleaned, the product is conveyed into a product runner through a vibration disc; c, the product falls to a precise damping weighing device from the product runner and then is weighed; d, the product is subjected to first-step buffering through a buffering device; e, buoyancy damping is conducted on the product through a water pressure buoyancy damping device; f, feeding into corresponding graded packaging bags according to different grades; by arranging the spring damping device, the supporting disc is buffered through damping of a mechanical spring, so that a product above the supporting disc is prevented from vibrating the supporting disc, and the weighing speed and the weighing stability are improved; and the water pressure buoyancy damping device is arranged, and the supporting disc can descend and ascend more slowly through water pressure buoyancy damping, so that reciprocating motion caused by damping is avoided, and the supporting disc can be better and rapidly stopped stably for weighing.