Abstract: At the background of explosive growth of geological big data, combing the bottleneck of practical application of online big data map services, this paper studies the problems of balanced decomposition of computational domain for real-time rendering of geological big data.A series of optimization schemes are carried out, including automatic collection of time samples for vector map service, automatic statistics of worktime, vector map gridding, grid-based visual field partition, multi-threaded parallel rendering, merging rendering results, etc.The results are obtained in the response rate of vector large data online services.