Necrotizing soft tissue infections (NSTIs) encompass a wide spectrum of infections involving the epidermis, dermis, subcutaneous tissue, and muscle, clinically presenting as cellulitis, fasciitis, or myositis, with recent studies reporting mortality ranging from 16% to 34%. Hyperbaric oxygen therapy (HBOT) has been commonly used as an adjunctive treatment for NSTIs to reduce morbidity and mortality. Its action is multifactorial, for example, by increasing oxygen delivery, direct antimicrobial effect, anti-inflammatory action, and wound healing. Evidence from the meta-analyses of nonrandomized studies involving large populations of patients with NSTIs shows that HBOT as an adjunctive therapy reduces the risk of dying, without causing any significant adverse event related to treatment. The 10th European consensus conference recommends the use of HBOT in NSTIs. Considering the rarity of the disease and limited availability of HBOT across health care facilities, high-quality randomized controlled trials need to be carefully designed to establish the dose and efficacy of HBOT in NSTIs.