Introduction The informal workers in Bangkok had inequity in social welfare and employment security, and they were the lowest group of happiness level than another area. Some of them were living with Non-Communicable Diseases (NCD). Therefore, this study aims to improve health status of the NCD informal workers by applying self-management method.

Method This study composed of quantitative and qualitative studies. The 15 informal workers were included by criteria. They were participated in the Mental health improvement project, had NCD risks or NCD patients, living in Bangkok, and willing to improve health status. The Participatory-action research was applied in this study by giving the knowledge of self-management (composed of 1) appropriate sleep 2) long breathing 3) reduce dessert consumption 4) do light physical activity) and relevant knowledge (including environmental improvement, finding assistant, finding more knowledge, making inspiring sentence, and self-rewarding). The progressive of health status were collected by in-depth interview and self-administrative questionnaire during June, 2015-October, 2016. The nonparametric statistics was applied in data analysis.

Results After all subjects were trained in self-management, they set up their target plan and followed it periodically. The results showed that 4 Diabetes Mellitus workers succeed in control of weight and blood sugar and 1 could maintain her weight. One worker with Diabetes Mellitus and Hyperlipidemia, 3 workers with Hypertension, and 3 Over-weight adults succeed in weight control, 2 workers with Cancer could live without any progressive of cancer, 1 worker with Coronary Heart disease succeed in weight control and had better heath check up. Their stress score were reduced significantly (p-value=0.01), and their happiness score become increased.

Discussion Self-management and relevant knowledge are the important preventive factors of NCD prevention and there should be combined with the effective follow-up measure. However, this finding should be applied in large scale or in community.