Abstract: In order to gain a stronger competitive advantage, most platform-based E-commerce companies would absorb logistics service companies into their own ecosystem and choose to cooperate with professional logistics service companies. According to their in-depth cooperation, the types of cooperation between platform-based E-commerce enterprises and logistics service enterprises can be divided into two models: facultative symbiosis model and specific symbiosis model. Regardless of the model, the collaborative stability of platform-based E-commerce enterprises and logistics service enterprises is subject to such factors as the enterprise's survivability, leadership coefficient and collaborative contribution coefficient, etc.. Through the simulation analysis, it is further understood that although the two symbiosis models can increase the market revenue level of the platform-based E-commerce enterprises and the logistics service enterprises, the synergistic effect of the facultative symbiotic model is greater than that of the specific symbiotic model, which indicates that the stability of cooperation between the platform-type E-commerce enterprises and the logistics service enterprises is better over their partial business cooperation. This point can also give light to the platform E-commerce enterprises which currently depend entirely on the cooperation with logistics service enterprises for their logistics business that they should pay more attention to maintaining the stability of the collaborative relationship with logistics service enterprises, and achieve sustained and healthy development of both parties by giving full play to the corporate leadership and collaborative contribution.

Key words: platform-based E-commerce enterprise, logistics service enterprise, symbiosis, collaboration, stability