A lipstick case structure includes a base on which a rotary tube is mounted in conjunction with a guide tube having a spiral guide slot. The guide tube is fitted over the rotary tube such that the guide tube moves along with the base. The rotary tube is provided at the top end with a guide seat which is fastened to a casing. A flexible cover is movably disposed between the guide tube and the casing such that a protrusion of the flexible cover is slidably received in the spiral guide slot of the guide tube, and that a protruded block of the flexible cover is slidably received in an upright guide slot of the casing. The relative rotation of the casing and the guide tube results in movement of the flexible cover to obstruct an opening of the casing, or to keep clear of the opening of the casing.