A microfluidic nucleic acid detection kit, comprising a kit body and a reagent card, wherein the kit body and the reagent card are interconnected; the microfluidic nucleic acid detection kit further comprises a plurality of cavities and a plurality of flow channels, the plurality of flow channels communicates with the plurality of cavities; the plurality of cavities and the plurality of flow channels form a closed system; the plurality of flow channels at least comprises a gas source flow channel, a sample injection flow channel and an exhaust gas flow channel; and the plurality of cavities at least comprises: a gas source cavity configured for controlling a gas pressure of the closed system through a volume change; a liquid cavity configured to inject a liquid reagent, wherein the liquid cavity communicates with the gas source cavity through the gas source flow channel; a nucleic acid amplification cavity arranged on the reagent card, wherein the nucleic acid amplification cavity communicates with the liquid cavity through the sample injection flow channel; a gas tail cavity arranged on the reagent card; and a first sealing membrane arranged on the reagent card, wherein the first sealing membrane seals the sample injection flow channel, the exhaust gas flow channel, and the gas tail cavity; characterized in that the gas source cavity and liquid cavity are arranged in the kit body; the gas tail cavity communicates with the nucleic acid amplification cavity through the exhaust gas flow channel; the kit body is configured to slide relative to the reagent card to control the microfluidic nucleic acid detection kit to work, wherein before the kit body slides relative to the reagent card, the gas source cavity and the gas tail cavity have the same gas pressure, so that liquid in the liquid cavity does not flow into the nucleic acid amplification cavity; when the kit body slides relative to the reagent card, the gas source cavity is compressed, the gas pressure in the gas source cavity increases to push a liquid reagent in the liquid cavity to be injected through the sample injection flow channel into the nucleic acid amplification cavity, and the flow of the liquid reagent pushes a gas in the nucleic acid amplification cavity to be injected into the gas tail cavity. a gas source cavity configured for controlling a gas pressure of the closed system through a volume change; a liquid cavity configured to inject a liquid reagent, wherein the liquid cavity communicates with the gas source cavity through the gas source flow channel; a nucleic acid amplification cavity arranged on the reagent card, wherein the nucleic acid amplification cavity communicates with the liquid cavity through the sample injection flow channel; a gas tail cavity arranged on the reagent card; and a first sealing membrane arranged on the reagent card, wherein the first sealing membrane seals the sample injection flow channel, the exhaust gas flow channel, and the gas tail cavity; characterized in that the gas source cavity and liquid cavity are arranged in the kit body; the gas tail cavity communicates with the nucleic acid amplification cavity through the exhaust gas flow channel; the kit body is configured to slide relative to the reagent card to control the microfluidic nucleic acid detection kit to work, wherein before the kit body slides relative to the reagent card, the gas source cavity and the gas tail cavity have the same gas pressure, so that liquid in the liquid cavity does not flow into the nucleic acid amplification cavity; when the kit body slides relative to the reagent card, the gas source cavity is compressed, the gas pressure in the gas source cavity increases to push a liquid reagent in the liquid cavity to be injected through the sample injection flow channel into the nucleic acid amplification cavity, and the flow of the liquid reagent pushes a gas in the nucleic acid amplification cavity to be injected into the gas tail cavity.