This paper mainly studies the solubility changes of hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]-benzoate (DHHB), the most widely used sunscreen agent in different oils. Phenylethyl benzoate (226) oils have the greatest compatibility with DHHB sunscreens. After ultrasonic dissolution, the solubility is 0.241 g/mL when placed for 28 days at room temperature at 25 °C. The effect of different dissolution methods on the recrystallization of sunscreens was investigated, and it was found that the decline rate of the 28-day heating and dissolution was more than 10% lower than that of ultrasonic dissolution. It was reduced by 12.65%; the solubility changes of sunscreens were stored for 4 weeks under different storage temperatures (4℃, 25℃), and it was found that low temperatures were more likely to promote the crystallization of sunscreens. By adding emulsifiers Span 20 and Span 80, it is found that the addition of emulsifiers can significantly slow down the decline rate of the solubility of DHHB in the oil dioctyl carbonate (CC). The decline rate of the post-80s was reduced by 21.28%. By observing the crystallization behavior of sunscreen agents and XRD detection of recrystallized substances, the influence of the above conditions on the crystallization of DHHB was explored, which provided guiding significance for solving the application of DHHB in the later development of sunscreen products.