In response to the slow gold leaching rate and low gold leaching rate during the heap leaching process of a fine-grained dissemination,slimy,oxidized gold ore in Guizhou,the on-site production process was optimized.Based on ore process mineralogy research and heap condition experiments,combined with the actual production on-site,the main reasons hindering the gold recovery during the heap leaching process were diagnosed.These included the presence of gold minerals in fine particle form,low dissociation degree of mineral monomers,high content of easily sliming minerals,poor permeability of ore heaps,low pH value and cyanide mass fraction in leaching solution,and high spray intensity.Corresponding optimization measures were formulated to address the problems in the production process.After on-site renovations,the gold leaching rate increased from 35 % to 57 %,achieving the expected optimization effect and providing significant economic benefits for the company.