South American champions River, whose side cost only around 5 million euros ($5.43 million) in transfer fees, did enough to worry the European champions for the first half hour but were never in the contest after falling behind.
Messi, playing against an Argentine team for only the second time in his career, showed superb control to turn in Neymar's header after 36 minutes.
Uruguay forward Suarez burst clear of the River defence four minutes after halftime and headed another from a pinpoint Neymar cross to take his tally in the tournament to five goals.
No one is superior to Messi in Barcelona: Suarez
River, backed by 15,000 fanatical supporters, made a promising start with Rodrigo Mora and Lucas Alario both getting into good shooting positions but producing weak efforts which were easily saved by Barcelona goalkeeper Claudio Bravo.
Messi had already been denied by Marcelo Barovero before scoring the opener and his goal was the cue for Barcelona to take the game by the scruff of the neck.
The European champions, fielding six South American players in their starting lineup, sliced through the River defence and looked as if they could score with almost every attack as they went on to win the title for the third time.
COMMENTS
Comments are moderated and generally will be posted if they are on-topic and not abusive.
For more information, please see our Comments FAQ