Abstract: Government data open has gradually been popular around the world. However, problems still exist in China's data open. For example, some related concepts have not been clarified, government data open has not yet been separated from government information disclosure and reusing, as well as original ideas and methods have not yet been proposed. To highlight the practical contribution and realistic foothold of the government data open, its concept discrimination and comparison were studied and its significance and relationship with smart city construction were summarized aiming at dealing with the above problems. The analysis and comparison of government data open status in the world shows that government data open in China is still in the initial stage, where some strategies, such as continuing to promote policies and strengthen the guidance of social practices need to be learnt from foreign countries. An innovation way of government data open, which called “release first and constrain afterword” with social forces involved in was proposed and demonstrated.