Hydrogels are a frequently utilized and modified biomaterial. Due to their unique tissue-like properties, they are used in various biomedical applications. Among the many types of hydrogels, bioadhesive hydrogels are of particular interest, as they provide long-term robust tissue adhesion that aids in therapeutic applicability, including drug delivery, mechanical stimulus, and in situ monitoring and diagnosis. Accordingly, this review highlights recent developments in bioadhesive hydrogels and their dermatological applications. To provide a broader view of bioadhesive hydrogels, studies regarding their assistance in skin diagnosis and the corresponding treatments are also summarized. This review comprehensively explains the importance and versatility of advanced and unique therapeutic bioadhesive hydrogels used in skin care and therapy.