As a new social e-commerce model, community group purchase of fresh agricultural products has been gradually welcomed by the public. However, its development and operation still face homogeneous competition problems. In order to enhance competitive advantages of operators, this paper proposes a collaborative optimization mechanism, including a new pricing model and a new cold chain vehicle route planning model. It aims to ensure the quality of fresh products, reduce logistics costs, and improve enterprise profitability. The model takes into account not only the quality of fresh products and their impact on price and demand but also the impact of quality changes on total distribution costs. A two-layer programming method is applied to realize the collaborative optimization mechanism, and then the upper and lower models are solved by mathematical derivation, proof methods, and optimization procedures, respectively. Finally, the feasibility and effectiveness of the model are verified by combining with specific examples, and the following conclusions are obtained: price, delivery quality, and total profit increase with the increase of potential market demand rate. The lower the refrigeration temperature of the vehicle we choose within a certain range, the higher the quality can be obtained. In order to obtain the highest profit, community group purchase operators can choose a higher distribution temperature on the premise that they can guarantee that the quality of fresh agricultural products can be at an appropriate level.