Abstract: In this paper, the concept of composite layer topology and time varying topology is proposed on the basis of space time composition. Composite layer topology expands the sense of space time composition to spatial topology, and proves that the static spatial topology representation capability of composite layer topology is as strong as that of static layer topology. Time varying topology is an expansion of composite layer topology, which can explicitly represent topology change of spatial entity over time dimension. This formal representation of topology change forms a fundamental and complete representative capability for time varying topology.