The present disclosure discloses a time service and positioning network system for an underground chain-shaped large space in a coal mine. The system adopts a base station-level network internal time synchronization method which takes an optical fiber time service as a main part and takes a satellite time service as an auxiliary part to construct a time service and positioning network system with an unified time within the ad-hoc network base stations, based on the ad-hoc network base stations linearly arranged in the underground chain-shaped large space in the coal mine. Through the network construction, the network stabilization and the network application, the system unifies the time reference of the base station-level network and improves the positioning accuracy of the network application by utilization of the base station-level network internal time synchronization method. The system integrates the time service and positioning network system suitable for the underground coal mine and expands the network applicability based on an existing underground communication ring network.