A manufacturing method of an activated-carbon filter element has the steps of preparing a non-woven cloth, spreading activated-carbon powders, combining the activated-carbon powders with the non-woven cloth, and winding. In the step of spreading the activated-carbon powders, the activated-carbon powders are scattered onto the non-woven cloth by a scattering device. In the step of combining the activated-carbon powders with the non-woven cloth, the non-woven cloth is hot pressed by a hot pressing cylinder, and is melted. The activated-carbon powders are securely combined with the non-woven cloth.