The Uruguayan striker is the Premier League's leading scorer with 22 strikes and is one of the front runners for the accolade this season.
"The PFA Player of the Year isn't about the most morally perfect person so Suarez has every chance of winning," Barnes told Absoloute Radio.
"Yes, Van Persie has been fantastic but he's in a great side. If you're talking about players that have made the most impact for their club and the squad that they are in I would say Suarez has to be a favourite.
"Everything outside of football is minor when you're judging on the player's ability."
Suarez was signed from Ajax in Janaury 2011 for a reported fee of £22m.