Abstract: An image capturing device with a focusing assembly comprises a case formed by an upper casing and a lower casing; a cover for sealing the lower casing; an lower side of the cover having an opening for capturing images of outside objects; a base installed at a connection between the upper casing and the lower casing; an image sensor installed at a lower side of the base for capturing images through an opening of the front cover; a focus adjusting unit including an object lens, an adjusting wheel, an inner tube and an outer adjusting tube; the outer adjusting tube being located within the lower casing and has a longitudinal retaining groove at an inner side thereof; the inner tube being received in the outer adjusting tube; the inner tube having a helical groove; an outer side of the adjusting wheel having a post for driving the adjusting wheel.