Tickets may only be purchased via authorised channels. Tickets may only be purchased via authorised channels.
Tokyo 2020 Olympic urges all prospective ticket purchasers to be aware of unauthorised or potentially fraudulent ticket offerings.
About how to buy Olympic tickets 2020, it will be sale from Apr 2019 but
no tickets are currently available as of Jan 2019.
Tokyo Olympic 2020 official website FAQ.
Q：When and how will tickets for the Olympic and Paralympic Games be put on sale?
A： No decision has yet been made regarding ticket sales. Once this has been finalised, details will be made available on the official website of the Tokyo 2020 Organising Committee. As a point of reference, London 2012 and Rio 2016 began ticket sales approx. 18 months before the Games, and conducted sales in various stages.
[How to buy Olympic tickets 2020] Tokyo 2020 Announces Outline of Olympic Games Ticket Prices
"Those living outside of Japan will be able to order their tickets through the National Olympic Committee of their respective country or their authorised ticket reseller. "