James also delivered 11 rebounds and seven assists on Friday for the Cavaliers, who shot 56 percent from the field and improved to 4-5 on the season.
The 32-year-old American sank 23 of 34 shots -- including two three-pointers -- and made all nine of his free throw attempts in front of a crowd of 20,100 at the Capital One Arena in the US capital.
"I don't want to give myself a ceiling. I don't want to cap myself," said James, who recorded his first 50-point game since returning to his hometown Cavaliers. "I want to be as complete a basketball player as I can be.
"Even rounding 33 I feel I am in the best shape of my career. I am out here, I might as well keep getting better."
Derrick Rose added 20 points for the Cavaliers, who lost three games during their four-game losing skid by double digits.
Both teams were struggling heading into Friday's game as the Wizards only added to their woes, having now lost four of their last five.
Bradley Beal scored 36 points for Washington. John Wall had 13 points and 15 assists as the Wizards shot 53.6 percent from the field.
James, who is in his 15th NBA season, finished just four points shy of his career-high 61 set in 2014 against the Charlotte Bobcats.
But there is also something about playing the Wizards that seems to bring out the best in James.
In February, James banked home the game-tying three point shot in the closing seconds of regulation and Cleveland went on to beat Washington 140-135 in overtime in a contest that some considered to be the league's 2016-17 regular-season game of the year.
Wall and Beal told reporters earlier on Friday that they believe Cleveland purposefully dropped out of the top seed in the playoffs last season to avoid facing Washington in the early rounds.
James played like someone who took that slight to heart.
On Friday, he scored 24 points and Cleveland shot 65.8 percent from the field in the first half for a 74-66 lead.
- 'On fire' -
"Nothing that we did was going to work," Wizards coach Scott Brooks said. "The guy was on fire. That's what happens certain nights with great players."
Elsewhere, Kyrie Irving finished with 25 points as the Boston Celtics rallied from a double digit deficit to defeat the Oklahoma City Thunder 101-94 and extend their winning streak to seven games.
Irving scored 15 of his points in the fourth quarter. Forward Al Horford also rose to the challenge and finished with 20 points for Boston.
Paul George led the Thunder with 25 points, while Russell Westbrook had 19 points, six rebounds and 11 assists.
In Atlanta, James Harden had 29 points and 11 assists before sitting the fourth quarter as the Houston Rockets bombed away early from three-point range to beat the Atlanta Hawks 119-104.
Harden was six of 11 on three-point shots, and the Rockets took 47 of their 89 shots from behind the arc, making 16.
The Rockets had lost seven straight overall to the Hawks and hadn't won in Atlanta since 2012.
Elsewhere, Kristaps Porzingis had 37 points as the New York Knicks clawed their way back to .500 with a 120-107 win over the Phoenix Suns.
source: news.abs-cbn.com
