Service perception analysis is the crucial solution to understand user experience and network quality, and the maintenance and optimization of the mobile networks. With the fast development of mobile Internet and OTT(over-the-top) services, the traditional network-centric mode of network operation and maintenance is no longer an effective way. In this situation, how to effectively evaluate and optimize user's service perception is getting more and more important. The key factors that impact on user's end-to-end OTT service perception is analyzed based on the so-called crowd sourcing based user perception monitoring methodology. Furthermore, the inner relationship among the key factors and the interaction between key quality indicators are evaluated from several aspects, by utilizing big data set of user perception collected from large amount of smart phone users in the real network. The results of analysis are highly valuable references for the improvement of user perception and network quality, network deployment and optimizations, etc.