Leaching agent for gold ore dressing and dump leaching method

The invention discloses a leaching agent for gold ore dressing. The leaching agent comprises a pretreatment agent and an environment-friendly gold extraction agent. The pretreatment agent comprises the following raw material components: a complex microbial inoculant, ammonium sulfate, water, potassium chloride, dipotassium phosphate, magnesium sulfate, calcium nitrate, porous starch microspheres and the like. The complex microbial inoculant is obtained by mixing streptococcus, pseudomonas wrinkles and bacillus cereus; the environment-friendly gold extraction agent comprises urea, sodium bicarbonate, mineral salt, coke, sodium sulfide, sodium lignin sulfonate and other raw material components. When the leaching agent for beneficiation of the gold ore is used for dump leaching, carbonaceous gold ore is crushed and heaped to form an ore heap; the method comprises the following steps: firstly, spraying an ore heap with the oxidation treatment liquid, then spraying the ore heap with the pretreatment liquid, then s