Although marine vibrio wound infections and septicemia are being reported with increasing frequency, description of the histopathologic changes has been scanty. The histologic alterations in three patients with primary marine vibrio wound infections are presented. The lesions are characterized by intense acute cellulitis of the subcutis with much tissue destruction and extension into the adjacent dermis. The superficial dermis is devitalized and lacks an inflammatory cellular infiltrate. Subepidermal noninflammatory bullae are formed. Many organisms are seen both within the areas of intense acute inflammation and in devitalized areas. Organisms and inflammation are especially oriented around vessels, with associated acute vasculitis. It is concluded that the morphologic picture in marine vibrio wound infections is nonspecific yet characteristic.