Argentine forward Cesar Delgado scored twice in the second half as slick-passing Monterrey dominated the tournament's first quarter-final in snow-sprinkled Toyota.
Jesus Corona opened the scoring after nine minutes, finishing a superb three-man move from close range before his back-heel fell for Delgado to tap home in the 77th minute.
Delgado smashed in his second seven minutes later to kill off the game, in which Hawk-Eye's goal-line technology was being used for the first time, although Ulsan grabbed a late consolation through Lee Keun-ho.
Monterrey could have scored more but showed enough to suggest they will be no pushovers for Chelsea when the teams meet in Yokohama on Thursday.
Egypt's Al-Ahly were playing J-League champions Sanfrecce Hiroshima in Sunday's second quarter-final for the right to face Brazil's Corinthians in the last four.