To analyze the improvement of clinical symptoms and recovery of neurological function in adult Japanese encephalitis, and study the prognostic factors. Follow-up was conducted for 112 hospitalized patients with Japanese encephalitis (JE) in adults at the Department of Neurology of three hospitals in Gansu province from July to October 2016, from July to October 2017, 6 months and 1 year after onset, respectively. The neurological functional recovery was evaluated by modified Ranking Scale (mRS).The influencing factors were analyzed by logistic regression model. Among the 112 adult patients with JE after 1year follow-up, 57% (64/112) were completely recovered (mRS score=0), and 14%(16/112) had mild neurological dysfunction (mRS score=1 or 2 points), 20% (22/112) had moderate to severe neurological dysfunction (mRS score 3 to 5), and 9% (10/112) died. In 102 survivors, decreased consciousness were fully recovered (100%), 75% of the mental and behavior disorders, 64% of cognitive/memory impairment, 71% of language function disorder, 61% of paralysis, 73% of extrapyramidal symptoms were fully recovered, and 92% of the seizures were controlled. Comparison of clinical data of initial on-set between good prognosis group (mRS score≤2, 80 cases) and poor prognosis group (mRS score>2, 32 cases) showed that initial clinical manifestation with seizures, consciousness (GCS score), cerebrospinal fluid pressure, and lesion of MRI involved in midbrain had statistically significant differences (all 0.05) . Multivariate analysis demonstrated that cerebrospinal fluid (CSF) pressure>250 mmH(2)O and lesion of midbrain in MRI were independent risk factors of poor prognosis in adult patients with JE. JE is an acute and infectious viral encephalitis of the central nervous system with high disability and mortality. Most patients were completely recovered, and some had neurological sequelae. CSF pressure>250 mmH(2)O and lesion of midbrain in MRI are independent risk factors for poor prognosis.