Pituitary adenomas in childhood and adolescence are relatively rare. In the present study we investigated intratumoral hemorrhage in pituitary adenomas and examined cases of intratumoral hemorrhage using adult patients for comparison. From 1975 to 2012, 38 consecutive patients operated for pituitary adenoma and one patient treated with medication alone, were enrolled in this study. Their ages were less than 18 years old at the initial diagnosis (mean age 15.3 ± 2.9 years). The comparison group consisted of 209 consecutive adult patients (>18 years old). The incidence and characteristics of intratumoral hemorrhage in pituitary adenomas were evaluated, based on magnetic resonance imaging (MRI) findings (28 cases) and on operative findings. The incidence of pituitary adenomas in childhood and adolescence was 38/1,073 (3.5 %) patients operated. Functioning pituitary adenomas (82.1 %) were common and non-functioning pituitary adenomas (17.9 %) were rare. Although no significant difference in tumor size was found and Knosp grade did not differ between young (≤18 years old) and adult (>18 years old) patients, indications of intratumoral hemorrhage on MRI was common in young patients (42.9 %). Based on both MRI and operative findings, intratumoral hemorrhage was significantly more likely to occur in young patients, compared with adult patients.