Butler is regarded as one of the top individual defenders in the NBA and has often matched up with James in the past. The No. 3 seed Bulls are set to face the No. 2 seed Cavaliers in Game 1 of the Eastern Conference Semifinals on Monday.
"He really is a talented player in this league, but I don’t think that intimidates me, not to the slightest bit," Butler said, according to K.C. Johnson of the Chicago Tribune.
Butler, 25, averaged a career-high 20.0 points and 5.8 rebounds per game this season while shooting 46.2 percent from the field.
James, 30, is in his first season back with the Cavaliers after spending the previous four seasons with the Miami Heat.