The invention provides a single-direction detonating door element with a delay function and a using method thereof. The single-direction detonating door element comprises an outer shell, delay bodies, an explosive-proof body and booster explosives. The delay bodies belong to existing finished industrial products, the delay bodies are cylindrical metal bodies, and the delay bodies are made of metal with high ductility. The outer shell is cylindrical, the two ends of the outer shell are opened, and the inner surface of the outer shell is in interference fit with the explosive-proof body. Long enough cavities are reserved between the two ends of the outer shell and adjacent end openings so that detonating fuses can be inserted in the cavities to be fixedly connected, and the detonating fuses can also be fixedly connected in the way that the two ends of the detonating fuses are provided with rubber plugs and sealing elements and a detonating guide tube and a fiber detonating cord are inserted into a hollow structure. Each delay body comprises one cylindrical metal body, the outer cylindrical surface of each delay body is in interference fit with the inner wall face of the explosive-proof body, a delay powder core is arranged at the center of each cylindrical metal body, and specific delay time is achieved by controlling the length of the delay powder cores and the burning time of delay powder. A traditional detonating fuse does not have the delay function, the element has the delay function, the design of a detonating network is simplified, the cost of a detonating device is lowered, and the safety performance of network design is improved.