Infection is the most common complication of atopic dermatitis (AtD). In particular, some patients with AtD exhibit increased susceptibility to skin infections of bacterial, viral, and fungal etiologies. In some cases, infections can even be systemic. Bacterial skin infections are more common than viral and fungal ones. An especially severe infection caused by the herpes virus is herpetic eczema, which can cause life-threatening complications. Infections of fungal etiology are represented mainly by the Malassezia species, especially in patients with dermatitis of the head and neck. The review focuses on the pathophysiological mechanisms identified to date that are thought to predispose to skin infections. The main ones are impaired skin barrier function, complex immunological changes, as well as poorly understood factors such as environmental exposure and skin dysbiosis. The review also includes the clinical characteristics of patients with various skin infections, as well as appropriate treatment for complications of AtD.