Disclosed are: an arm regeneration device for controlling hydraulic oil supplied to an arm cylinder during grading work by the combined movement of a boom and an arm; and a control method. According to the present invention, provided is the arm regeneration device for construction equipment, comprising: first and second hydraulic pumps and a pilot pump; an arm cylinder connected to the first hydraulic pump; a first control valve for controlling hydraulic oil flow supplied to the arm cylinder during switching; an arm operation lever; a boom cylinder connected to the second hydraulic pump; a second control valve for controlling hydraulic oil flow supplied to the boom cylinder during switching; a boom operation lever; an arm regeneration valve provided to a path between the meter-in-port of the first control valve and the hydraulic oil tank; an arm regeneration cut valve for releasing a regeneration function by switching the arm regeneration valve by the hydraulic oil supplied from the pilot pump during switchin
