Abstarct: Mineralogical studies including identification of valuable and gangue minerals, texture, relationship between ore and gangues, size, and degree of liberation are the first stage of mineral processing operation and have very important effect on the improvement of current mineral processing technology. In this research, mineralogy studies, ore chemistry and degree of liberation from the point of view of mineral processing was performed on the processing plant feed of Gushfill Pb-Zn mine. Gushfill mine is located at the Iran Kuh Mining area, 20 km SW Isfahan. Sphalerite, galena and pyrite are the main minerals observed by optical microscope, in association with black shales, dolomite, barite and quartz as the gangues. Clay minerals such as mica, illite and kaolinite were characterized by X-ray diffraction. baxsed on ICP-Ms results the content of Cd and In were determined 2.3 and 62.2 ppm, respectively. Fe-rich sphalerite in the Zinc flotation sample was identified by micro Raman spectroscopy. In order to investigate the degree of liberation and to select the best size range, the samples were crushed and grinded and then divided in to 8 size fractions. In the dimension range of 105-149 microns, the maximum degree of liberation was determined 69% and 66% for galena and sphalerire, respectively. baxsed on XRD analyses, quartz, muscovite, galena and sphalerite were the main minerals in the mentioned dimension range. The results obtained from flotation experiments indicated that the recovery of Pb and Zn increased with decreasing the particle size. Also, the results showed that the highest recovery rate of lead (61.89%) and zinc (87.88%) achieved in the range of 105 to 149 micron.