Objective:To explore the characteristics of illness perceptions and its effect on quality of life in adult epileptics.Methods:A cross-sectional study was conducted to evaluate 98 adult patients with epilepsy and 75 diabetic patients hospitalized at the same period.The Chinese illness perception questionnaire revised edition(CIPQ-R) was used to evaluate the differences in illness perception factors between the two groups.The quality of life in epilepsy-31(QOLIE-31) was used to assess the quality of life of 98 adult epilepsy patients and 55 healthy people, and the correlation analysis and multivariate regression analysis were used to investigate the effect of illness perceptions on the quality of life of epileptic patients.Results:The emotional representations factor score of CIPQ-R in the epilepsy group(21.73±5.79) was higher than that in the diabetes group (18.76±5.42) ( P<0.01). The scores of timeline acute/chronic, personal control and illness coherence factors of CIPQ-R in the epilepsy group((16.47±4.68), (20.91±4.03), (15.21±4.44)) were lower than those in the diabetes group ((19.16±4.75), (22.68±3.90), (16.56±3.73)) ( P<0.05). The scores of multiple factors in the quality of life scale of patients with epilepsy were lower than those in healthy controls( t=-2.264--8.203, P<0.01). Correlation analysis showed that the emotional statement dimension and consequences factors in CIPQ-R were significantly negatively correlated with the total scores of QOLIE-31 and all the other factors it belongs to ( r=-0.202--0.527, P<0.05); the identity, timeline acute/chronic, and timeline cyclical factors in CIPQ-R were negatively correlated with the total score of QOLIE-31 ( r=-0.272--0.342, P<0.01); the treatment control and illness coherence factors in CIPQ-R were positively correlated with the total score of QOLIE-31 ( r=0.259, r=0.307, P<0.01). Multiple stepwise linear regression showed that the identity, timeline acute/chronic, consequences, timeline cyclical, and emotional representations factors were important factors influencing the quality of life of adults with epilepsy. Conclusion:Adult epileptics have certain negative illness perceptions.Among them, identity, timeline acute/chronic, consequences, timeline cyclical and emotional representations factors have significant effects on the quality of life of adult epileptics.