The first poll of top-flight players in the summer era, carried out by Rugby League World and players association 1eague3, also reveals that over a third have dealt with depression.
"It's certainly an issue for Super League," St Helens and England forward Jon Wilkin, chairman of 1eague3, told Rugby League World.
"To have 75 per cent say that they have an interest in leaving the competition is very significant.
"We knew it was an issue, with the amount of press that the Burgess boys have been getting in Australia and everything around the England RU set-up with guys like Chris Ashton.
"There seems to be a lot of positive momentum towards leaving the game in this country and that's something that we need to address."
Wilkin added: "To see that 34 per cent of the players that replied have had an issue with depression and that it's played a part in their professional rugby career, for me was a shockingly high statistic.
"It underlines the relevance of the State of Mind round and their campaign, as well as all the great work that both Sporting Chance and the RFL are doing.
"It also shows that being a professional sportsman is not all peaks - there are plenty of troughs in there."
The poll attracted responses from over 150 players - almost half of the total involved in Super League and over 60 per cent of 1eague3's membership and Wilkin believes it is time for players' views to heard.
"One of the big issues for us is that players' opinions have never really been taken seriously in the game," he said.
"Individual players have been asked their opinion but they are usually the high-profile players who have had good careers within the game.
"This survey gave us the opportunity to cover all bases and hear what young and old players alike think about the big issues in the game, whatever their profile is.
"I found some of the results really surprising - they certainly weren't what some of my pre-conceived ideas were."