Objective To explore the different characteristics of clinical characteristics and neuroendocrine of the elderly hospitalized patients with acute bipolar and unipolar depression. Methods A total of 60 elderly patients with unipolar depression （unipolar group） and sixty patients with bipolar depression （bipolar group）， with the same structure of gender， age， and education background were collected from June 1， 2018 to September 30， 2019. Self-made questionnaire was used to collect clinical features， neuroendocrine， and Hamilton Depression Scale （HAMD）， and Min-mental State Examination （MMSE）. Intergroup univariate analysis and multivariate logistic regression analysis were performed to analyze the influencing factors of the incidence of elder patients with bipolar depression. Results The onset age of patients in the bipolar group ［（43.35±16.04） years］ was smaller than that of the unipolar group ［（54.40±14.36） years］； t=3.975，P＜ 0.01； The total course of disease was longer than that of the unipolar group ［（23.50 （11.25，37.25） years and 7.00 （1.00， 16.75） years； Z=-4.301，P＜ 0.01］. The number of hospital admissions was greater than that of the unipolar group ［（2（1， 3）