Abstract: A liquid depth measuring device for measuring the depth of a liquid in a tank or other receptacle is disclosed. The device includes a vertically arranged outer housing member having a tubular central body portion, a tapered valve seat at the lower end of the body portion, and an annular sliding bearing member at the upper end of the body portion. The device further includes a tubular inner housing member mounted for longitudinal sliding movement through the bearing and extending in concentrically spaced relation within the outer housing member to form an annular space therebetween. A tapered valve member adapted for sealing engagement with the valve seat is carried at the lower end of the inner housing member, and a graduated measuring tape is arranged longitudinally within the inner housing member.