The utility model discloses a space combined supporting structure of a water-rich fractured stratum tunnel. The utility model relates to the technical field of tunnel construction, in particular to awater-rich broken surrounding rock section structure, and solves the problems that conventional shotcrete-anchor supporting surrounding rocks adopted by water-rich broken surrounding rock sections areeasy to deform greatly, bear large surrounding rock pressure, are difficult to effectively prevent and control water leakage and endanger tunnel structure stability and construction safety. The mainpoints of the technical scheme are as follows: the structure comprises an initial concrete layer, a reinforcing mesh and steel arches arranged at intervals, longitudinal connecting steel beams which are distributed in a staggered mode along the axis of the tunnel are arranged between the steel arch frames in the circumferential direction. The longitudinal connecting steel beams are connected withanchor rods; a steel fiber concrete layer covering the steel arch frame, the reinforcing mesh and the longitudinal connecting steel beams is sprayed on the surface of the reinforcing mesh; a waterproof and drainage structure layer is laid on the surface of the steel fiber reinforced concrete; and a secondary lining concrete layer is poured on the surface of the waterproof and drainage structure layer. The method has the advantages that surrounding rock deformation in the tunnel can be effectively controlled, the excellent waterproof and drainage functions are achieved, and tunnel structure stability and construction safety are guaranteed.