In order to explore the influence of rise-span ratio on the mechanical properties of Pipe-Roof Pre-construction (PRP) structures in underground engineering, mechanical tests on two PRP structure members were designed and completed with rise-span ratio as a parameter. Through the comparative analysis of load-deflection curves and strains of steel pipe curtain and concrete section, the failure process and failure mode of different rise-span ratio specimens were explored, and the influence of rise-span ratio on the mechanical properties of members was analyzed. A numerical calculation model was established to further explore the influence of rise-span ratio, concrete strength and reinforcement ratio on the bearing capacity of the PRP structure arch members. The results show that with fixed end constraints, the bending failure mode of the PRP structure arch members is presented under symmetrical concentrated load. The change of rise-span ratio has a great influence on the bearing capacity of the PRP structure arch members. When the rise-span ratio increases from 0.048 to 0.102, the ultimate bearing capacity and stiffness of the members become larger. The concrete strength and reinforcement ratio have little effect on the ultimate bearing capacity of the members.