The invention provides an unfreezing device, a refrigerator and an unfreezing control method of the refrigerator. The unfreezing device comprises a shell, a first electrode board, a second electrode board and a high-frequency power supply, the first electrode board is arranged at the top of the inner wall of the shell, the second electrode board is arranged at the bottom of the inner wall of the shell, the first electrode board and the second electrode board are connected with two ends of the high-frequency power supply respectively, high-frequency alternating electric fields are generated between the first electrode board and the second electrode board when the high-frequency power supply operates, so that high-frequency electromagnetic waves are generated and acted onto unfrozen food, insulating materials are arranged between the first electrode board and the inner wall of the shell and the second electrode board and the inner wall of the shell and on the lower side of the first electrode board and the upper side of the second electrode board, and the unfrozen food is placed on the insulating materials of the upper side of the second electrode board. The unfreezing device is simple in structure, the high-frequency electromagnetic waves are rapidness and uniformity in unfreezing, and nutrient loss is low.