The invention relates to a device and a method for drawing farmland soil leakage water. The device comprises a leakage water collecting pipe, a water inlet pipe, a drawing device and a water outlet pipe, wherein the drawing device comprises a handle, a cylinder wall sealing part, a piston hinge sealing part and a base one-way flow part, the cylinder wall sealing part comprises a felt dustproof ring, a cylinder wall cover and a cylinder wall, the piston hinge sealing part comprises a piston rod, an elastic collar for a hole, a knuckle bearing, an elastic collar for a shaft, a piston, seal rings and a guide sleeve, and the base one-way flow part comprises a base, an O-shaped seal ring, conical valve cores, a pipe joint, a non-porous spring plug, a porous spring plug, a spring, a water inlet and a water outlet; the collecting pipe and the drawing device are connected through the water inlet pipe, a sampling bottle and the drawing device are connected through the water outlet pipe, the handle of the drawing device is pushed and pulled to drive the piston to move up and down in the cylinder wall, the pressure difference is formed between a rod-less cavity in the cylinder wall and the outside, so that two conical valve cores of the base part begin to act in sequence, the one-way valve principle is formed, and the farmland soil leakage water is drawn. With the adoption of the device and the method, the leakage water collection operation is simple, carrying is convenient, and the practicability is high.