In August 2018, the World Down Syndrome Congress will be held at the SECC for four days.
It will be the first time the conference, which will attract around 1200 delegates, will be held in Scotland.
Down's Syndrome Scotland made the bid for the congress in partnership with Glasgow City Marketing Bureau, the Scottish Council for Voluntary Organisations and VisitScotland.
The congress is held every three years and brings together people with Down's syndrome, their parents and carers, professionals, practitioners, researchers and organisations.
It is expected to generate around 6000 hotel room nights in the city.
Andrew Boys, director of Down Syndrome International, said: "Applications were received from organisations in five countries, .
"Following lengthy scrutiny and discussion DSi is delighted to announced Down's Syndrome Scotland has been successful and we look forward to working with them."
The Glasgow bid was the first to use the city's new People Make Glasgow brand, which was launched in June.
The bid was was led by Andrew Macintyre, 26, Stuart Campbell, 27 and Sam Ross, 25, each of whom have Down's syndrome.
Glasgow City Council leader Gordon Matheson said: "The city is looking forward to warmly welcoming delegates from all over the world for this prestigious meeting."
Pandora Summerfield, chief executive of Down's Syndrome Scotland, said: "We look forward to providing a broad spectrum of information sessions showcasing the latest discoveries in research and best practice as well as fringe events for the general public."