Neisseria sicca is considered part of the normal flora of the oropharynx. Although usually believed to be a harmless saprophyte, it has rarely been recognized as an etiologic agent in human disease, particularly in immunodeficient hosts. Two immunodeficient women are described in whom N. sicca pneumonia of the left lower lobe developed. One patient was 30 years old and had just completed a full-term pregnancy, and the other patient was 73 years of age and was receiving prednisone for bullous pemphigoid. Each had an uncomplicated pulmonary course, the pneumonia being successfully treated with penicillin or cephalothin. Only one patient with N. sicca pneumonia has been previously described in the literature. The significance of N. sicca pneumonia is discussed on the basis of a review of findings in these three patients. Although unusual N. sicca should be considered among the organisms causing pneumonia in immunodeficient patients.