The invention relates to a gynecological collagen lotion and a preparation method thereof. The gynecological collagen lotion is prepared from 0.5-10% of glycerinum, 0.5-10% of propylene glycol, 0.5-10% of cocamidopropyl betaine, 0.01-0.2% of menthol, 0.01-0.1% of collagen, 0.01-2.0% of fructo-oligosaccharide, 0.1-2% of hydroxyethyl cellulose, 0.01-0.5% of polyhexamethylene biguanide hydrochloride,0.01-0.3% of ethylparaben, 1-5% of plant extracts, 0.01-2% of lactobacillus leavening and the balance of purified water till 100%. Due to adoption of the cocamidopropyl betaine and the plant extractsas main raw materials, and by virtue of synergetic functions of the raw materials and auxiliary materials, the gynecological collagen lotion which is good in treatment effect and free of irritation to vulvae can be prepared, and the product has remarkable antibacterial effects on escherichia coli, staphylococcus aureus, candida albicans and the like, and is capable of preventing propagation of harmful bacteria and maintaining cleanliness and health of the vulvae.