Abstract: Objective: To observe the clinical effects and safety of the pituitary adenoma resection by nasal transsphenoidal approach under microscope.Methods: The pituitary adenomas in 115 patients were resected by nasal transsphenoidal approach under microscope.The relationships between the size,endocrine type,resection range of the tumor and clinical effects,and the influence factors of the postoperative complications were retrospectively analyzed.Results: All patients were followed up for 1 to 2 years,81 cases were cured,20 cases were eased,12 cases recurred and 2 cases died.The cure rate of microadenoma was higher than that in large adenoma and huge adenoma(P<0.05).The cure rates of PRL adenoma,adrenocorticotropic hormone adenoma,growth hormone adenoma and mixed adenoma were higher than that in non-function adenoma(P<0.05).The cure rates in patients treated with total and subtotal excision were higher than that in patients with partial excision(P<0.05).The complications recurrence of the functional pituitary adenoma was sighificantly lower than that of the non functional pituitary adenoma.Conclusions: The clinical effects of the pituitary adenoma resection by nasal transsphenoidal approach are good,which are related to the size,functional type and excision range of tumor.