The 1976–77 Guinness National Basketball League season was the fifth season of the National Basketball League.
The league was sponsored by Guinness and the number of teams participating remained at ten. The Embassy All-Stars relocated to Milton Keynes, Cleveland became Durham and Bedford replaced Leeds.
The Crystal Palace team completed a second consecutive double of National League and Cup and were beginning to achieve national public recognition. There were no playoffs for the League during this era and Carl Olsson was awarded the season MVP award.