An electric soldering iron capable of finely adjusting tin amount comprises a plug, an electric soldering iron grab handle, a rubber ball, an internal heating pipe, a hollow soldering handle, a soldering iron head and a soldering tin pushing mechanism. A rubber ball support is arranged in the electric soldering iron grab handle, the rubber ball is clamped between a supporting portion of the rubber ball support and a hole of the electric soldering iron grab handle, one end of the electric soldering iron grab handle is provided with the internal heating pipeline which is connected with the hollow soldering handle, a tin feeding guide rail is arranged in the soldering iron head, one end of the soldering iron head is provided with a heating unit with a hollow pipe, the hollow soldering handle is connected with the heating unit with the hollow pipe, and the soldering iron head is internally provided with the soldering tin pushing mechanism which is mounted between the heating unit with the hollow pipe and the tin feeding guide rail of the soldering iron head. The tin amount is controlled through the soldering tin pushing mechanism of the soldering iron head, and is finely adjusted through the rubber ball on the handle if tin is excessive, so that a soldering gun needs not to be used for sucking unnecessary soldering tin. Therefore, tin consumption can be reduced greatly, and utilization rate of the tin is increased.