The Portuguese superstar scored in the 12th, 28th, and 81st minutes of the game, while Tottenham's Harry Kane converted a penalty in the 35th minute at Old Trafford. Manchester United's Harry Maguire scored an own goal in the 72nd minute.
After the game, Ronaldo reached 806 career goals, breaking Josef Bican's 805-goal record.
The 37-year-old attacker, who was not included in the starting 11 in the previous league game, scored 15 goals in 30 games this season.
Five-times-Ballon D'or winner won five UEFA Champions League titles, in 2008 with Manchester United, in 2014, 2016, 2017, 2018 with Real Madrid, three Premier League titles with Manchester United in 2007, 2008, 2009 and two La Liga trophies with Real Madrid in 2012 and 2017 throughout his astonishing career.
Ronaldo also won the 2016 European Championship with Portugal.
Manchester United are in fourth place with 50 points, 19 points behind league-leading rivals Manchester City. Tottenham Hotspur are in the 7th spot with 45 points in the Premier League standings.
Premier League Results:
Brighton-Liverpool: 0-2
Brentford-Burnley: 2-0
Manchester United-Tottenham: 3-2