The development of Facebook in Viet Nam has created social online forums for many discussions. The topic of dissatisfaction of public service attracted the most posts and comments. Our study showed that, the dissatisfaction, claims on public service will be one of the most useful sources for improving public services. Under the approach of social listening by the technique of opinion mining/sentiment analysis we found many interesting insights relating to citizens‟ responses on public health services. Facebook big data was archived from 2017 to 2018 and analysed in three dimensions: timeline, word ranking topics and sentiment analysis. We hoped that the result could provide public service managers with solutions for minimizing dissatisfaction towards public service and manage the image of public health services. | Opinion and dissatisfaction towards public services on the internet the case of Vietnamese public health services
