Staphylococcus lugdunensis (S. lugdunensis) is an unusually virulent coagulase-negative staphylococci (CNS) and uncommon cause of infective endocarditis (IE) involving mainly native left sided valves. S. lugdunensis IE, which was described previously as "surreptitious" and "wolf in sheep's clothing", runs an aggressive course with a high rate of severe in-hospital complications. Therefore, early surgical treatment has been considered for the treatment of S. lugdunensis IE. However, we experienced a case of S. lugdunensis pulmonary endarteritis which was cured with antibiotic therapy alone.