Objective To investigate the clinical features of sleep disorders in adult patients with epilepsy and depression and related influencing factors.Methods A cross-sectional study was performed and Beck Depression Inventory-Ⅱ (BDI-Ⅱ) was used for the evaluation of 100 patients with epilepsy. The Pittsburgh Sleep Quality Index (PSQI) and Epworth Somnolence Scale (ESS) were used for evaluating the patients with epilepsy and 50 healthy adults strictly matched for age and sex.Results Of all 100 adults with epilepsy, 30 had depression, resulting in a comorbidity rate of 30%. The patients with epilepsy and depression had significantly higher global PSQI and ESS scores than the patients with epilepsy alone and the control group (global PSQI score: 5.93±1.41 vs 2.09±1.38 and 0.94±0.91, P<0.05; global ESS score: 6.57±4.48 vs 3.79±1.98 and 2.30±1.53, P<0.05). The multivariate regression analysis showed that in the patients with epilepsy and depression, global PSQI score was correlated with the course of disease and seizure control (t=4.279 and 2.406, P<0.05), while global ESS score was correlated with the course of disease and seizure type (t=6.662 and 2.645, P<0.05).Conclusions Adult patients with epilepsy and depression have an increase in the degree of daytime lethargy and a reduction in sleep quality, and the severity of sleep disorders is closely associated with the course of disease, seizure control, and seizure type.