Microfluidic nucleic acid extraction device and method based on FTA (fault tree analysis) card

The invention relates to a microfluidic nucleic acid extraction device and method based on a FTA (fault tree analysis) card, and the device comprises a sample introduction unit, an extracting unit, a collection unit and a power device; the sample introduction unit includes multiple reagent containers and a first control valve, wherein the multiple reagent containers are respectively loaded with a variety of sample introduction components for making a nucleic acid extraction liquid, the first control valve connects the multiple reagent containers and can switch the reagent containers to allow the reagent containers to be connected to the extracting unit, the first control valve is connected with the power device, the power device provide power for liquid or gas flow among the sample introduction unit, the extracting unit and the collection unit, the extracting unit is internally provided with a containing space for embedding the FTA card, the collection unit includes an extraction liquid collecting container for collection of the nucleic acid extraction liquid; the whole device is simple and convenient to complete nucleic acid extraction operation, fast in extraction, and convenient for preservation and analysis of nucleic acids, can handle complex samples, and has the advantages of simple preparation and low cost.