Necrotizing fasciitis is an uncommon rapidly progressing infection of soft tissue characterized by a severe inflammation of the fascia and soft tissue. The disease is associated with necrosis and subcutaneous gangrene of the inflamed tissue with systemic toxicity that carries a significant mortality unless timely diagnosed and aggressively treated. Monomicrobial necrotizing fasciitis caused by Pseudomonas aeruginosa is an exceptionally uncommon condition with only few cases reported in the literature so far. We are reporting a six-month-old female infant who was previously healthy and who presented with necrotizing fasciitis and isolates Pseudomonas aeruginosa both from the blood and tissue. The child improved after the intensive treatment.