The basketball tournament at the 1989 SEA Games took place from 21 to 25 August 1989. This edition of the tournament featured both men's and women's tournament. All matches took place at Stadium Negara in Kuala Lumpur.
After the round robin tournament, Malaysia, by virtue of defeating the defending champions the Philippines, won the championship for their second title since the 1979 edition. The Philippines would continue winning gold in these tournaments until their streak was broken in the 2021 SEA Games.
Meanwhile, Thailand, after being undefeated in the women's division, won their first ever championship, thus ending the hosts Malaysia's reign of six-time defending champions.
