The present invention relates to a method of preparing fermented herbal eye drops, and the method includes an herbal medicine washing process of mixing an herbal medicine mixture, vinegar, and coarse salt in purified water, allowing it to stand, and then washing it; a heating process of inputting the herbal medicine mixture washed through the herbal medicine washing process into a decoction pot, mixing the herbal medicine mixture with purified water, and heating the herbal medicine mixture mixed with purified water; a cooling and fermentation process of cooling decoction prepared through the heating process and then fermenting the decoction; an eye drop raw material extraction process of distilling a fermented product prepared through the cooling and fermentation process to extract raw materials for eye drops; and an alkaline water mixing process of mixing alkaline water with the raw materials for eye drops prepared through the eye drop raw material extraction process. The fermented herbal eye drops prepared through the above process do not contain chemical components, have low cytotoxicity, are safe for the human body, and have an excellent sterilizing effect, thereby improving eye diseases such as inflammation or redness.