Glioblastoma multiforme (GBM) is the most lethal subtype of glioma, classified as a WHO grade 4 infiltrative glioma. The etiology of GBM remains unknown and risk factors can be identified only in a small minority. We report the synchronous occurrence of GBM in an otherwise unrelated married couple, i.e. a husband and his wife, who developed GBM within an interval of 1 month. No specific causative environmental factors were identified for both patients, and the genetic screens were negative for hereditary syndromes. Family history was negative for tumors, and no other incidence of cancer in either siblings, parents or other children was reported. An analysis of the couple's exposure to nonionizing electromagnetic fields and ionizing radiations revealed values within the normal ranges usually found in homes. Overall, conjugal tumors are rarely reported. However, the case reported herein raises important questions about possible etiologic factors.