Jamaican sprint star Shelly-Ann Fraser-Pryce will also run in the 200m when she defends her Olympic 100m title in Tokyo next year.
It is set to be the final Olympics for Fraser-Pryce, who will be 33 on Friday.
"I will be doubling up definitely," she was quoted as saying in Kingston by website Inside the Games.
"Last year [season] I really wanted to attempt the double but my coach had other plans so I just worked with that plan. He knows best."
Fraser-Pryce's Olympic best at 200m was a silver medal at London 2012, although she did triumph at that distance in this year's Pan American Games.
Her main rivals in the 200m in Tokyo will include Britain's Dina Asher-Smith, who is fresh from winning gold at that distance in the recent World Championships in Doha - but took 100m silver behind Fraser-Pryce at the same championships.