Purpose Pituitary abscess (PA) is rare and commonly described in case reports or small case series. This study aimed to better determine salient clinical manifestations related to the diagnosis and appropriate treatment of PA using by far the largest case series of this disease. Methods A total of 6361 consecutive patients underwent surgery for pituitary diseases in Peking Union Medical College Hospital between January 1991 and December 2013. Among this cohort, sixty-six patients were diagnosed with PA based on both intraoperative findings and postoperative histopathological evidence. Results The most common clinical presentation was anterior pituitary hypofunction (81.8 %), followed by common headache (69.7 %), diabetes insipidus (DI; 47.9 %), visual disturbances (45.5 %) and symptoms related to infection (43.9 %). Forty patients (66.7 %) showed typical rim enhancement after gadolinium injection on magnetic resonance imaging (MRI). Most patients (63 of 66, 95.5 %) underwent transsphenoidal surgery (TSS), and the remaining 3 patients (4.5 %) were treated with transcranial surgery (TC). After follow-up for 7.2 +/- 4.9 years, PA was diminished in most patients (81.8 %), as demonstrated by post-operative MRI, and eight patients underwent at least one additional operation due to recurrence. Conclusions For patients with hypopituitarism and DI with rim enhancement on MRI, we should consider the possible diagnosis of PA. Proper use of antibiotics, complete drainage via surgery and hormone replacement for hypopituitarism are the key treatments for PA.