Background and purpose: To investigate the clinical prognosis and vascular outcome of ischemic stroke patients with isolated symptomatic middle cerebral artery stenosis, and further analysis of the predictors associated with the results. Methods: Ischemic stroke patients aged 18-55 years old with isolated symptomatic middle cerebral artery stenosis were evaluated and followed up prospectively for six months. Logistic regression was used to detect predictors of ipsilateral stroke recurrence, and factors associated with the dynamic changes of lesion vascular were analyzed. Results: Eighty patients were included, with a mean age of 41.8 +/- 8.3 years old. Males predominated in this cohort at a proportion of 78.8% (63/80). Twenty percent of patients presented with ipsilateral ischemic stroke recurrence during this time but mostly with a good outcome (70% mRS 1); multiple logistic regression indicated that diabetes mellitus is an independent predictor for stroke recurrence; 38.6% patients presented with significant vascular changes during the follow-up, with progression in 12 (17.1%) and regression in 15 (21.4%) patients individually. No variables were detected as predictors of cerebral vascular progression. Conclusion: Isolated symptomatic middle cerebral artery stenosis in young adults had unaccepted high rates of recurrence but comparatively good prognosis; despite the dramatic change of lesion artery in the short period after stroke, no factors were detected as the probable factors associated with the dynamic process.