Abstarct: The ever-increasing demand for gold element in the world has caused its recovery from various ores, especially sulfide-resistant ores, to increase. Cyanidation is one of the hydromextallurgical processes However, it leads to many environmental problems, and for this reason, many efforts have been made to replace this method. Recent research works have shown that the use of glycine (C₂H₅NO₂) in gold ore leaching reduces the consumption of the leaching agent. In this research, using mineralogical studies and XRD, XRF, and ICP-OES analyses, it was determined that the ore is refractory and contains a large amount of sulfur. Before performing the leaching process, pretreatment was conducted by roasting in three stages, which the highest recovery of gold in the solution after the third stage of roasting (during 8 hours and at a temperature of 800 °C) was 85.16%. Optimal leaching parameters for gold extraction were determined using Design Expert 12 software and response surface method (RSM). The results indicated that the highest gold recovery was with 0.63 mol glycine concentration of obtained 94.37%. Additionally, in order to confirm the validity of the model, three confirmation experiments were conducted at the predicted optimum conditions, which the Maximum of gold recovery for three experiments was achieved 93.14%. In the last stage of this research, by keeping the parameters of optimal conditions of Design Expert software in two stages, the experiment of reducing cyanide consumption was done In the first stage tests, gold leaching tests (four tests) were performed Without glycine and changing the concentration of cyanide at 500 ppm, 1000 ppm, 1500 ppm, and 2000 ppm. The gold recovery was obtained 75.54%, 80.48%, 85%, and 90.4%, respectively. In the second stage tests, gold leaching tests (four tests) were performed by keeping glycine concentration constant at 0.63 mol and changing cyanide concentration at 200 ppm, 400 ppm, 500 ppm, and 750 ppm. The gold recovery was obtained 80.5%, 84.03%, 85.28%, and 92.1%, respectively. In general, it can be concluded that the presence of glycine in cyanide leaching has a positive effect and reduces the consumption of cyanide.