Nadal's six trophies this year include a record 10th title at the French Open and a third at the US Open. The last time the Spaniard won at least six titles in a year was in 2013, when he captured 10 trophies for the season.
Kyrgios struggled with his serve to start the match and never found a confident range. His first-serve percentage mostly languished under the 50 percent mark.
In contrast, Nadal always looked in charge and saved all four break points he faced.
"I was playing very high intensity the whole match, changing the directions and not making many mistakes," Nadal said.
Kyrgios offered Nadal eight break points in the first set, with Nadal taking two service breaks.
Kyrgios was angered by a line call in the first set, and his complaints eventually cost him a penalty point at the start of the eighth game.
The Aussie player didn't make it onto the board in the second set until he was serving with Nadal already leading 5-0.
"In the semifinal I played well, obviously beating Alex [Zverev]," Kyrgios said. "It's a typical type of week for me: beat a player well, then pretty much no-show."
The last time Kyrgios played a No. 1 it was also against Nadal. In that 2014 Wimbledon fourth-round encounter, the then-144th-ranked Kyrgios emerged a four-set winner.
This was Nadal's second China Open title in four trips to the final. He won his first in his Beijing debut in 2005.
"In 2005, I never will believe that I will keep playing tennis in 2017," Nadal said.
Nadal leads Kyrgios 3-2 in career meetings and is 2-1 against him this season.