A gemini surfactant, N,N'-dilauroyl ethylenediamine sodium dipropionate (DNET), was applied as a novel collector for improving the flotation separation efficiency of hemimorphite from quartz. Flotation tests of hemimorphite separation from quartz with DNET were carried out to determine the flotation performance. The adsorption mechanism of DNET on the hemimorphite surface was analysed based on zeta potential measurement, Fourier transform infrared (FTIR) spectroscopic analysis, and XPS detection. The results indicated that DNET had strong collecting ability on hemimorphite. When the DNET dosage was 175.0 mg/L and the slurry pH was 6.83, more than 84% of the hemimorphite could be floated. The quartz recovery was less than 8.00% in the experimental process. The artificially mixed mineral separation results demonstrated that DNET could effectively separate hemimorphite from quartz. The flotation separation results showed that the grade and recovery of zinc were 49.40% and 99.61%, respectively, when the DNET dosage was 150.0 mg/L and the slurry pH was 8.56. The adsorption mechanism analysis indicated that chemical adsorption occurred between DNET and the Zn site on the hemimorphite surface.