0353 GMT October 04, 2022
World number two Murray was seriously tested by his Bulgarian opponent but the Scot ended a near-faultless week in Beijing with the main prize, BBC reported.
British number one seed Murray did not drop a set during the tournament.
Earlier, British number one Johanna Konta was beaten 6-4 6-2 by Agnieszka Radwanska in the women's final.
"Andy is one of the toughest competitors out there and the credit goes to him," said Dimitrov after the match on Sunday.
Relive finals day at China Open
World number 20 Dimitrov made it through to the final after his semifinal opponent, Milos Raonic, was forced to withdraw with an ankle injury.
It looked a formality for the Briton who broke his opponent's serve in the opening game before holding his own to double the advantage at the beginning of the first set.
Dimitrov rallied in the second set, forcing it to 5-5 before the final headed into a tie-breaker.
Murray gained the mini-break with the first point and although Dimitrov hit back, the Scot won six of the next seven points to earn his maiden China Open title.
Murray narrows Djokovic's lead
Murray has targeted overtaking Novak Djokovic as the world's top-ranked player and, with the Serb missing the China Open through injury, the Scot has narrowed the gap.
While Murray has triumphed at Wimbledon and the Olympics this year, Djokovic's form has dipped since beating his rival to the French Open title.
Djokovic was beaten in the early rounds at Wimbledon and Rio 2016, and although he reached the US Open final last month, he was beaten by Switzerland's Stan Wawrinka.