The invention discloses a field runoff water and soil loss prevention and control device and a field runoff water and soil loss prevention and control method. The field runoff water and soil loss prevention and control device comprises a metal cylinder, wherein a metal cover is screwed at the top end of the metal cylinder; a collecting hopper communicated with the interior of the metal cover is arranged on one side of the top end of the metal cover; ventilation holes which are annularly distributed at equal intervals are formed in the top end position of the side wall of the metal cylinder; and a metal shield is welded to the top end position of the side wall of the metal cover, a metal mesh hopper is arranged on the inner wall of the metal cylinder at a position close to the bottom ends of the ventilation holes in a sleeving manner, a round hole is formed in the bottom end of the metal mesh hopper, a metal hopper is welded to the inner wall of the round hole, a metal outer cylinder iswelded to the top end position of the side wall of the metal hopper, and a sewage drainage pipe is welded to the bottom end of the metal hopper. The field runoff water and soil loss prevention and control device and the field runoff water and soil loss prevention and control method can realize water and soil separation, can monitor the soil amount conveniently v an arranged tension sensor, prevents rainwater and external soil from flowing into the metal cylinder by means of the arranged metal cover and ventilation holes in a matched mode, and reduces external interference.