Walker, who was Rovers chairman from 1991 until his death in 2000, invested millions of pounds into the infrastructure of the club as well as funding glamorous signings of the likes of Alan Shearer and Chris Sutton.
Parkes, nicknamed 'Mr Blackburn' having spent 35 years at the club, is fearful for Rovers' future under the current Indian ownership.
He told the Lancashire Telegraph: "Jack Walker would be turning in his grave. It is like the complete opposite happening now to what happened with Jack Walker.
"Jack was in it because he loved Blackburn Rovers and loved the town, Venky's aren't. I have to admit I don't know why they are in it at the moment.
"Jack built the stadium, built the training ground. He knocked down houses for car parking but gave the residents top dollar. You don't know why Venky's are here."
Shearer, who was the club's top goalscorer when they lifted the Premier League title in 1995, has also expressed his dismay at the owners' "awful stewardship".