Astana gained 103 votes against 44 for Liege during a meeting of the BIE, which has 161 member states. The fair will be held from June 10 to September 10, 2017.
Resource-rich Kazakhstan, Central Asia's largest economy, has been under President Nursultan Nazarbayev's rule since 1990.
The BIE selects hosts for two kinds of exhibitions, international and universal. Smaller three-month long "International Expositions" are held in between the five-yearly six-month-long Universal Expositions,
The first Universal Exposition was staged in London in 1851 and since then they have served to showcase technology, architecture and culture, while attracting visitors to host cities and generating business.