OBJECTIVE： To explore the situation of knowledge-attitude-practice of medication （shorted for medication KAP） of elderly patients with chronic diseases and its relationship with depression mood. METHODS： Through using scale of medication KAP in elderly adults with chronic diseases and Self-rating Depression Scale （SDS）， a face to face questionnaire survey was conduceed among elderly patients with chronic diseases examined in two community service centers of Lanzhou. The Pearson correlation analysis was used to verify the correlation between the score of medication KAP and the score of depression mood，and multivariate stepwise linear regression was used to analyze the influential factors （including the items in the general data table and depression mood with statistical significance after single factor analysis） of the score of medication KAP. RESULTS： Totally 300 questionnaires were sent out， and 289 valid questionnaires were returned with effective feedback rate of 96.3％. The results of questionnaire investigation showed the average score of the KAP was （31.12±6.20）； the scores of medication knowledge， attitude and practice was （18.39±4.85）， （3.18±1.24） and （9.55±2.08）， respectively. The average score of depression mood was （39.99±6.06）， compared with 48.4％ （140 patients） with depressive symptoms. Pearson correlation analysis showed that the score of medication knowledge （r＝－0.356）， the score of medication compliance （r＝－0.465） and the score of medication KAP （r＝     －0.490） were negatively correlated with depression mood （all P＜0.01）. Multiple stepwise regression analysis indicated that the score of the KAP were affected by depression mood and demographic factors including family occupation， detailed monthly income in a family， the difference was statistically significant（P＜0.05）. CONCLUSIONS： In the community， the level of the medication KAP in elderly patients is mainly affected by depression mood and also by demographic factors. In the work of health care education for elderly patients with chronic diseases， medical staff should pay more attention to patients with depression mood and timely take targeted nursing measures to improve the level of the medication KAP.