Objective To analyze the etiology and clinical characteristics of 120 patients with oculomotor nerve paralysis. Methods The clinical data of 120 patients with oculomotor paralysis treated in our department from May 2019 to July 2021 were collected and analyzed, and the etiology, clinical characteristics and treatment results of all patients were summarized. Results All 120 patients had acute onset, 105 cases (87.50%) had monocular onset and 15 cases (12.50%) had binocular onset.All patients had different degrees of ptosis, exophthalmos, hypotropia, limited eye rotation and diplopia.The largest age composition among the selected patients was 41 ~ 60 years old (49 cases, 40.83%).Among 120 patients with oculomotor nerve palsy, 103 cases (85.83%) were clearly diagnosed, 17 cases (14.17%) were not, 23 cases (19.17%) were complete oculomotor nerve palsy and 97 cases (80.83%) were incomplete oculomotor nerve palsy.The most common causes were diabetes mellitus (18 cases, 15%), aneurysms (16 cases, 13.33%), and cerebral infarction (15 cases, 12.50%).After 3 months of continuous treatment, 88 cases (73.33%) were cured, 21 cases (17.50%) were improved and 11 cases (9.17%) had few changes. Conclusions The main causes of oculomotor nerve palsy were diabetes mellitus, aneurysm and cerebral infarction.The clinical manifestations could be varying degrees of ptosis, exophthalmos and strabismus, limited rotation of eyeball and diplopia.Most patients could be cured or improved after treatment.In clinical practice, a variety of diagnostic techniques and primary diseases should be combined to diagnose and treat those patients.