Two cases of allergic bronchopulmonary pseudallescheriosis (ABPP) are described. These are the first cases of this allergic bronchopulmonary mycosis (ABPM) reported in which the clinical and serologic criteria are described. The first case was in a patient with mild asthma, and it resolved spontaneously after expectoration of a mucous plug. The second was in a patient with recurrent allergic bronchopulmonary aspergillosis with an exacerbation of ABPM caused by Pseudallescheria boydii. The total serum IgE, IgG, and IgE antibodies against P. boydii and the clinical picture well define ABPP. This diagnosis may be important to recognize in order to prevent a progression of the patient's lung disease.