Background: and Purpose The relationships among interleukin (IL)-10 levels, anxiety, and cognitive status after stroke remain controversial. We aimed to determine the associations of serum IL-10 levels with poststroke anxiety (PSA) and poststroke cognitive impairment (PSCI). Methods: We recruited 350 patients with stroke, of whom only 151 completed a 1-month follow-up assessment. The Mini Mental State Examination (MMSE) and Hamilton Anxiety Scale (HAMA) were used to assess the cognitive status and anxiety, respectively. Serum IL-10 levels were measured within 24 hours of admission. Results: IL-10 levels were significantly lower in the PSA group than in the non-PSA group, and they were negatively associated with HAMA scores (r=-0.371, p<0.001). After adjusting for all potential confounders, IL-10 levels remained an independent predictor of PSA (odds ratio=0.471, 95% confidence interval=0.237–0.936, p=0.032). IL-10 levels were strongly correlated with behavior during interviews, psychic anxiety, and somatic anxiety. Patients without PSCI had higher IL-10 levels were higher in non-PSCI patients than in PSCI patients, and they were positively associated with MMSE scores in the bivariate correlation analysis (r=0.169, p=0.038), and also with memory capacity, naming ability, and copying capacity.However, IL-10 did not predict PSCI in the univariable or multivariable logistic regression. Conclusions Low IL-10 levels were associated with increased risks of PSA and PSCI at a 1-month follow-up after stroke. Serum IL-10 levels may therefore be helpful in predicting PSA.