Hexaconazole belongs to triazole demethylation inhibitors; Sterol demethylation inhibitors have extremely high antibacterial activity and broad-spectrum protection and treatment effects on diseases caused by fungi, especially basidiomycetes and ascomycetes. Destroy and prevent the biosynthesis of ergosterol, an important component of pathogen cell membrane, which leads to the failure of cell membrane formation and eventually leads to the death of pathogen. The medicine can effectively prevent and treat diseases caused by ascomycetes, basidiomycetes and fungi, especially diseases caused by basidiomycetes and ascomycetes, such as powdery mildew, rust, scab, brown spot, anthracnose, sheath blight and false smut, but has no effect on oomycetes and bacteria. The recommended dose is applied to suitable crops, which is environmentally friendly and safe for crops. Hexaconazole has permeability and systemic property. For example, if cross spraying is carried out in the middle of apple leaves, the penetration of chemicals into the thickness of leaves can alleviate the movement and redistribution, which has a good protective effect on untreated parts and bases.