Stephen Curry scored 26 points one game after a terrifying fall while Klay Thompson added 20 despite a laceration to his right ear for the top-seeded Warriors.
Golden State, who won 67 games during the regular season with rookie coach Steve Kerr, won the best-of-seven series 4-1.
The Warriors will meet the LeBron James-led Cleveland Cavaliers in the NBA Finals that starts next week. It is their first trip to the finals since 1975.
The Rockets had won Game Four of the series on Monday to avoid being swept, but were outscored 35-24 in the second quarter on Wednesday and played catch up the rest of the way.
Dwight Howard led the Rockets with 18 points and 16 rebounds, while James Harden, who scored 45 points on Monday, made just 2-of-11 shots and had 14 points to go with 13 turnovers.