United are planning to leave Old Trafford for a new 100,000-seat venue next door, with the development expected to cost around £2 billion. However, Edwards believes the club's immediate focus should be improving performances on the pitch rather than investing heavily in a new home.
The 81-year-old, who was chairman between 1980 and 2002 during a hugely successful period under Sir Alex Ferguson, has warned that stadium development will mean little if the team cannot attract supporters through its performances.
"There's no point in having a wonderful stadium if you can't fill it," Edwards said.
He also sympathised with supporters who have voiced their frustration at the stadium plans while United struggle in the Premier League.
"The crowd have been vociferous about what they could do with the new stadium. And I tell you what – I can sympathise with that.
"You can talk about new stadiums and everything else but the most important ingredient is always the players and what's happening on the field – and success."
Manchester United's recent difficulties have intensified scrutiny of the club's ownership and recruitment strategy. Michael Carrick's side had been enduring a nine-match winless run before their dramatic 3-2 Champions League comeback victory over Roma on Tuesday.
For Edwards, the priority is clear: the club must invest in the squad if it is to return to competing at the highest level.
"Now the last thing the United fans want to hear is a new stadium when they've got a team that is languishing 17th in the league, below Coventry.
"The priority has to be the team. Concentrate on getting that right. United now needs investment. I mean, they probably need investment on the stadium itself.
"So the club needs investment spending. The team definitely needs investment, doesn't it?"
Edwards also questioned whether the current squad has been assembled in the right way, suggesting that United's recruitment decisions deserve closer examination.
"When I look at the team sheet, I think, why isn't it performing? You know, there's some good individuals on that. It's down to choice. Did they need midfielders? Do they need a left-back or centre-forward?"
The former chairman was less willing to offer a definitive verdict on Carrick's position, acknowledging that assessing a manager's performance requires an understanding of what happens behind the scenes.
"I can't judge, you need to be inside to know. I was on the inside. I had knowledge the supporters didn't, which enabled me to make the right decisions. I still go to games. It's always special for me."
Speaking on Keys & Gray Unleashed, Edwards made clear that the club's sporting fortunes should come before the ambition of building a new stadium. His message to United's leadership is that a new venue will only mean something if the team gives supporters a reason to fill it.