The production efficiency of plastic gears is high, and their batches are large; while the traditional manual inspection is low and the accuracy is poor. To ensure product quality and production efficiency, a rapid sorting and inspection system for plastic gears was developed. The system was combined with a production line and used a conveyor belt for loading, a glass rotary for transmission, and a pneumatic device for sorting. Plastic gear images were captured using an industrial camera, and basic parameters such as the tip diameter, the hole diameter, and the concentricity were measured by a machine vision method; the tolerance ranges were compared, in order to judge the product quality. By using algorithms such as image segmentation, edge extraction, feature extraction, and defect identification, surface defects such as missing teeth, black spots, and burr were inspected. Finally, the system separated good and defective products according to the test results. The system could carry out fast, online, automatic, and non-contact separation and inspection. The test results showed that the measurement repeatability of the system was less than 0005 mm, the inspection speed was greater than 150 piece/min, the defect identification and sorting functions were accurate, and the system could run stably for a long time. Hence, the proposed system can meet the requirements of large-scale, high-efficiency, and high-reliability sorting and inspection at a plastic gear production site.