A screwing tool includes an engaging member adapted to be gripped as a handle including a first inserting member. A biasing member is received within the engaging member. A driving member includes a driving head and a guiding groove at two different ends. The guiding groove receives the first inserting member. The first inserting member interconnects the engaging member and the driving member. The biasing member is disposed between the driving member and the engaging member. A control ring receives the driving member and is selectively movable between a first position disposed at a first relative position with respect to the engaging member and in which the screwing tool becomes an impact screwdriver, and a second position disposed at a second relative position with respect to the engaging member and in which the screwing tool becomes a regular screwdriver. Link to USPTO.