Scientific advances have improved our understanding of the molecular pathological mechanisms underlying pituitary tumorigenesis, allowing us to analyze tumors in a more precise manner and to identify the tumors that have a greater risk of aggressive behavior at an earlier stage. Based on these molecular pathological findings, the classification of pituitary tumors has been revised over the last two decades to better describe their biological and clinical behavior and to identify prognostic markers of aggressiveness and poor prognosis. Understanding pituitary tumors at the molecular level has enabled increasingly targeted treatments with safety and efficacy validated in randomized trials. This paper reviews recent advances in the study of pituitary tumors, particularly pituitary endocrine tumors, and craniopharyngiomas, and describes potential therapies for pituitary tumors.