Water body sampling device and sampling method

The invention provides a water body sampling device. The water body sampling device comprises a reel, a throwing line, a counterweight, a water pumping device, a floating body and a water taking device, one end of the throwing line is wound on the reel, and the other end of the throwing line is fixed on the floating body; the bottom end of the floating body is connected with the counterweight through a connecting rope; the water taking device comprises a water taking pipe and a floating frame arranged on the throwing line in a penetrating mode. A battery, a driving motor and a clamping transmission assembly are arranged in the floating frame. The clamping transmission assembly comprises two pressing wheels which are clamped on the throwing line in a matched mode. The driving motor is used for driving the two pressing wheels to rotate at the same time, and the rotation directions of the two pressing wheels are opposite; the first end of the water taking pipe is fixed to the floating frame and connected with th