The invention discloses a radioactive waste resin interface measuring device based on a lifting device and an application method thereof. The measuring device comprises a resin storage tank, a density sensor arranged in the resin storage tank and a material feeding pipe arranged on the resin storage tank and further comprises a measuring instrument vertically stretching into the resin storage tank and in vertical rotating connection with the density sensor, a platform located above the measuring instrument and the lifting device. The measuring device and the method overcome the shortcoming of radioactive waste resin interface height error overbalance caused by the fact that the installation position of a measuring rod cannot be aligned right at a material feeding port, enable the position of the measuring instrument and the density sensor to have no relation with the position and the state of the material feeding pipe and are accurate in measurement.