Objective To investigate the knowledge of mood disorders and attitude towards the treatment of mood disorders among community residents in Shanghai, Wuhan, Harbin and Shenzhen. Methods From Jun. 2017 to Dec. 2019, outpatients from psychiatric hospitals and community health centers in Shanghai, Wuhan, Harbin and Shenzhen were recruited as the survey subjects, and were investigated by random sampling. A self-designed questionnaire on awareness of mood disorders was used to investigate the knowledge of mood disorders and attitude towards the treatment. In a face-to-face interview, the evaluators instructed the participants to download the “mood thermometer” mobile terminal (APP), and the participants completed the survey online. The awareness of mood disorders was investigated by multiple-choice questions. The frequency and cross-tabulation methods in multiple response analysis were used for analysis. Results The survey received a total of 1 289 valid questionnaires. The frequency of knowing the name of mood disorders from high to low was major depressive disorder (87.9%, 1 133/1 289), melancholic depression (57.3%, 739/1 289), mania psychosis (50.7%, 653/1 289), mania (40.1%, 517/1 289), bipolar affective disorder (23.6%, 304/1 289), manic-depressive disorder (23.1%, 298/1 289), mood disorder (22.6%, 291/1 289), manic episode (21.3%, 275/1 289), bipolar disorder (14.4%, 185/1 289), and hypomania (14.0%, 180/1 289). The recognition rates for typical cases of depressive disorder and mania were 61.5% (793/1 289) and 41.9% (540/1 289), respectively. Specialist clinics, women, students and on the job, divorce/separation and higher education level were associated with high recognition rates of depressive disorder and mania. The participants learned about the mood disorder knowledge through the Internet, television broadcasting, magazines and books, relatives and friends, and community publicity. Regarding the necessity of acquiring knowledge of mood disorders, 66.2% (853/1 289) of the participants thought that it was necessary, 30.7% (396/1 289) considered it was unnecessary, and 3.1% (40/1 289) chose not to answer. Regarding the attitude towards mood disorder treatment strategies, 62.2% (802/1 289) of the participants thought that psychotherapy and medication were needed, 13.9% (179/1 289) thought that psychotherapy only (or counseling) was needed, and 4.8% (62/1 289) thought that there was no treatment. There were significant differences in the attitudes towards the treatment strategies of mood disorders among the participants with different genders, occupations, marital statuses and education levels (all P＜0.01). The female, working, married/cohabiting, and lower educated participants believed that not only psychotherapy was needed, but also medication. Conclusion The overall awareness level of community residents in Shanghai, Wuhan, Harbin and Shenzhen on mood disorders, especially mania and bipolar disorder, is unsatisfactory. It is still necessary to strengthen the popularization and publicity of mood disorder knowledge, so as to improve the early recognition and standard diagnosis and treatment of mood disorders.