An azelaic acid gel, and a preparation method and an application thereof. The azelaic acid gel comprises the following components in percentage by weight: azelaic acid: 10-20%; salicylic acid: 0.5-2%; a polyacrylate cross-linked polymer-6: 1-3%; 1,3-propylene glycol: 60-74%; and the remaining part being water. The azelaic acid gel is used for preparing medicines for preventing or treating acnes.