De Gea came in for criticism following United's 2-1 defeat to Liverpool in the FA Cup at Anfield on Saturday.
Owen wrote on his Twitter account on Sunday: "One comment on yesterdays game. Don't agree with all this negativity towards De Gea.
"Admittedly he has made a couple of mistakes this season but listening to some people you would think he had a nightmare yesterday.
"I'm not having either goal was his fault. The problem is, once you get labelled, mud sticks and now any tiny mistake is magnified. Other keepers make similar mistakes and nothing gets said.
"The ball was on the 6 yard box for the first goal. He has to go for it. He also needs to watch the flight of the ball. There is then 6 players in front of him. There is nothing he could do. The free header was the problem, not the keeper.
"He couldn't do much with the second goal either. Is the problem not just a case of us not winning the first ball and not picking up a runner?
"In my opinion two bad goals to give away but to blame everything on the keeper is totally wrong. The lad will be a top keeper, he is only young. Harsh to blame him for everything.
"Must say, as you will be quick to remind me, I've watched a lot of home games this season! The support from behind both goals for him has been brilliant.
"The fans know he needs their support, his confidence needs boosting. I'm sure he will repay that support for years to come."