DNA sampling device for water environment and use method of DNA sampling device

The present invention discloses a DNA sampling device for a water environment. The DNA sampling device mainly comprises a first sampling column used for sampling large-volume DNA, a plurality of second sampling columns capable of completing sampling of small DNA from the first sampling column, a first sampling plate arranged at a middle end of the first sampling column in a penetrating manner, second sampling plates arranged at positions, close to bottom ends, of the second sampling columns in a penetrating manner, and a driving mechanism used for completing simultaneous sampling of the firstsampling column and the second sampling columns. Different DNA samples in a water body can be collected by simultaneous sampling through a plurality of the sampling columns, a use method is simple, suspended particles in the water can directly precipitate on a filter membrane during sampling, a step of precipitation after collection in the past is omitted, a sampling effect is better, a sampling speed is higher, and the m