The incidence of primary intracranial tumors in Manitoba, Canada was reviewed. From 1980 through 1985, 657 tumors were diagnosed. The crude incidence rates were 10.2/100,000 for males and 10.8/100,000 for females. The three most common tumors were: astrocytoma 281 (43%), meningioma 145 (22%), and pituitary adenoma 111 (17%). Average annual incidence rates for all tumors showed a bimodal distribution with one peak in the 0-4 age group (4.2/100,000), and the other in the 60-69 age group (27.2/100,000). For malignant astrocytoma, the age-specific annual incidence rate increased to the seventh decade where it reached a peak of 14.3/100,000. The incidence of benign astrocytoma remained relatively constant with age at 1.1/100,000. The annual incidence of meningioma increased with age up to the eighth decade reaching 7.2/100,000. Of the 145 meningiomas, 56 (39%) were meningotheliomatous, 48 (33%) transitional, 10 (7%) malignant, 7 (5%) fibroblastic, 6 (4%) psammomatous, 3 (2%) angioblastic, and 15 (10%) lacked pathologic diagnosis. The annual incidence of pituitary adenoma showed two peaks, the first occurring in the third decade (2.6/100,000) and the second in the eighth decade (3.2/100,000). Although the incidence of meningioma was relatively high, the clinical features and pathologic patterns of these tumors were not unlike those previously reported in the literature.