Winter is the season when psoriasis is prone to recurrence, especially in the dry and cold north. Although the etiology and pathogenesis of psoriasis are not fully understood, current studies show that the reduction of epidermal barrier function plays a role in the occurrence and development of psoriasis. Psoriasis patients have abnormal ceramide metabolism in epidermal lipids at the lesions, significantly less ceramidase, and increased cholesterol content in the scales, resulting in an imbalance in the ratio of various lipids, which ultimately reduces the epidermal permeability barrier function. From the viewpoint of the onset site, psoriasis is easy to occur in the epidermis vulnerable parts such as the back and the extremities, which often scratch and rub to destroy the barrier function of the epidermis, mental stimulation can also reduce the permeability barrier function of the epidermis, and the dry and cold northern weather can also cause the barrier function of the epidermis to be in a subhealthy state, which in turn will promote the recurrence of psoriasis. Therefore, improving the barrier function of epidermis can promote psoriasis recovery and help improve the therapeutic efficacy of psoriasis, and maintaining the optimal state of skin barrier function is also an important means to prevent the occurrence of psoriasis. It is recommended that psoriasis patients use medical skin care products to repair the barrier function of the skin as early as possible in winter to reduce disease recurrence and recover as soon as possible.