73 patients with bullous pemphigoid were studied to examine the association between serum anti-basement membrane zone (anti-BMZ) antibody and malignancy. Indirect immunofluorescence (IIF) was performed on the sera. 37 patients had positive IIF for anti-BMZ antibodies, ranging in titer from 1:20 to 1:10,230. On a follow-up of 7–41 months (mean 22 months), only 3 patients (8%) had malignancies (endometrium, bladder, squamous cell carcinoma of the skin). 36 patients had negative IIF for anti-BMZ antibodies. On a follow-up of 5–43 months (mean 16 months), 3 patients (8%) had malignancies (breast, colon, endometrium). No correlation between the presence or absence of anti-BMZ antibody in the serum and the development of malignant disease was observed.