A rechargeable power tool includes a direct current motor, a switching circuit, at least one speed setting unit, a duty ratio setting unit, a drive unit, an operation amount detecting unit, an abnormality determining unit, and a determination threshold setting unit. The abnormality determining unit compares an operation amount detected by the operation amount detecting unit and a determination threshold set based on the operation amount to thereby determine whether or not an operation state of the rechargeable power tool is abnormal. The determination threshold setting unit sets the determination threshold in a continuous or stepwise manner in accordance with a rotation speed set by the speed setting unit.