Los Angeles outfielder Enrique Hernandez struck three home runs, including a grand slam in the third inning, and drove in seven runs at Wrigley Field in Chicago.
Los Angeles will meet either the New York Yankees or Houston Astros in the World Series, which starts in Los Angeles on Tuesday.
The Yankees lead the Astros 3-2 in the best-of-seven American League Championship Series ahead of Game Six in Houston on Friday and, if needed, Game Seven on Saturday.
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The Dodgers have won the World Series five times since moving from Brooklyn to Los Angeles in 1958, most recently in their last trip to the 'Fall Classic'.
"Feels good to hear (the words) 'World Series,'" Los Angeles starting pitcher Clayton Kershaw said. "It's been a long time coming for this team. I never thought in a million years I'd get to play a World Series.
"I don't know how to compare it to years past but everybody has a role and everybody executes. It just seems like there's a different superstar every night."
While the Dodgers celebrated, the Cubs' season concluded with barely a whimper, 12 months after they ended a century-long drought by beating the Cleveland Indians in the seventh game of the World Series.
The Cubs were never in it on Thursday, as the Dodgers batters jumped all over Chicago starter Jose Quintana.
The Colombian left-hander barely made it out of the second inning, replaced by Hector Rondon with nobody out and the bases loaded in the third.
Rondon quickly struck out Logan Forsythe before Hernandez sent the first pitch he faced over the ivy wall to make the score 7-0, effectively ending the contest.
Hernandez matched a major league playoff record with seven RBIs, while every position player had at least one hit for Los Angeles as they racked up 16 in all, to the Cubs' four.
Kershaw got the win after giving up three hits and one run over six innings.
A three-times Cy Young Award winner for best pitcher in the National League, he improved his mediocre postseason record to 6-7, while the Dodger bullpen pitched three scoreless innings, extedning their streak to 23 consecutive scoreless innings.
Cubs manager Joe Maddon lamented his team's lack of offense in the series, but also complimented the Los Angeles pitching.
"Give the Dodgers credit, they pitched well, had a great plan, stuck to it, didn't walk anybody," he said.
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