A method for rapid detection of a target nucleic acid amplification product while preventing cross-contamination between target nucleic acid amplification products and avoiding false positives, comprising the steps of: placing an unopened reaction tube containing the target nucleic acid amplification product into an enclosed unit comprising an inner core and an outer casing, wherein the inner core comprises a fixing case part and a base, the fixing case part having two holes respectively for housing washing buffer vacuoles and a reaction tube containing an amplification product, wherein a sealing ring positioned between the hole for housing the reaction tube and the base ensures an intimate and sealed contact thereat, the base part comprising a washing buffer container having a vacuole puncture needle for puncturing the washing buffer vacuoles, an amplification product container having a blade for cutting the container, a sealing diaphragm between the units and, a piece of glassfiber paper disposed in the container elements and and connected to the bottom of a test strip, and a test strip sealing part having a test strip sealed therein and a transparent window for observing the test strip and the outer casing comprising a handle cover, a fixing case pressing part, a washing buffer vacuole extruding part, and a transparent window; closing the handle cover of the unit; pressing the handle cover of the detection unit until it is fastened down whereby the blade on the base is subjected to a pressing force by the fixing case pressing part so as to cut the reaction tube containing the applification product, and the washing buffer vacuole puncture needle on the base is subjected to an extruding force by the washing buffer vacuole extruding part so as to puncture the washing buffer vacuole such that the amplification product and the washing buffer are absorbed into a sample pad in the test strip via capillary phenomenon of the glassfiber paper whereby the detection process detects a specific antigen-antibody reaction between the amplification product and the test strip. placing an unopened reaction tube containing the target nucleic acid amplification product into an enclosed unit comprising an inner core and an outer casing, wherein the inner core comprises a fixing case part and a base, the fixing case part having two holes respectively for housing washing buffer vacuoles and a reaction tube containing an amplification product, wherein a sealing ring positioned between the hole for housing the reaction tube and the base ensures an intimate and sealed contact thereat, the base part comprising a washing buffer container having a vacuole puncture needle for puncturing the washing buffer vacuoles, an amplification product container having a blade for cutting the container, a sealing diaphragm between the units and, a piece of glassfiber paper disposed in the container elements and and connected to the bottom of a test strip, and a test strip sealing part having a test strip sealed therein and a transparent window for observing the test strip and the outer casing comprising a handle cover, a fixing case pressing part, a washing buffer vacuole extruding part, and a transparent window; closing the handle cover of the unit; pressing the handle cover of the detection unit until it is fastened down whereby the blade on the base is subjected to a pressing force by the fixing case pressing part so as to cut the reaction tube containing the applification product, and the washing buffer vacuole puncture needle on the base is subjected to an extruding force by the washing buffer vacuole extruding part so as to puncture the washing buffer vacuole such that the amplification product and the washing buffer are absorbed into a sample pad in the test strip via capillary phenomenon of the glassfiber paper whereby the detection process detects a specific antigen-antibody reaction between the amplification product and the test strip.