Provided is a channel simulator having a function of supporting a carrier aggregation and a carrier aggregation block used for the same to support a carrier aggregation function at a minimum path loss without reducing the number of valid connectable terminals. The channel simulator includes: a terminal interface block connected to each of at least four terminals through at least two transmission/reception ports; a carrier aggregation block including unit modules each including one RF coupler and one RF switch, and interposed between the terminal interface block and the terminal to support the carrier aggregation for one to four component carriers; and a management server. The carrier aggregation block includes a front-end carrier aggregation unit and a rear-end carrier aggregation unit.