There are a lot of fics where steve doesn’t know tony is iron
man but is there any fics where tony is the one that doesn’t know steve
is captain america?

This is actually one of my favorite things!  I mean, I love all identity
porn, but it is somehow even more delicious when it is Tony who has no
idea of Steve’s secret identity.  There are a good number of fics where
they don’t know each other’s identity, but I’m going to try to go with
the ones that focus more on not knowing Steve’s identity.  Anyway…here
you go!

DON’T HIDE YOUR LOVE, REVEAL IT WITH COMMENTS AND KUDOS!

Wait &Sea by Lenalena:
In which Tony and Steve get sent on an undercover mission aboard a
cruise ship to make contact with Hydra. In this AU the military has kept
the discovery and defrosting of Captain America a secret, so Steve and
Tony have never met before. Yet they are to pose as newlyweds….

Show Me How To Live by @imafriendlydalek​:
The world has moved on since Captain America went into the ice, Steve
had been told by his handler at SHIELD, an agent he knows only as
Sitwell. Genetic modification of humans is very much forbidden by
international law, and with the country already embroiled in war,
Captain America has to remain hidden.
It’s 2005 and Steve is back at
art school, this time in Boston. At an event that involves melting
metal, he sees a pair of familiar eyes. As they get to know each other,
Steve and Tony also learn the truth behind the lies they have been told.

Say When by @stark-spangled-lovers​: ** Iron Man 2 AU ⎪Undercover AU **** Can be read as a stand alone! **Book
1 of the Say When series. An alternate version of Iron Man 2. What if
Steve was unfrozen early? What if instead of Natasha, Steve got assigned
to help Tony while the genius was slowly dying of palladium poisoning?
What if he never revealed his identity to him until the very moment the
Avengers first came together, forming a team? (Why is this not tagged Identity Porn????)

A Face to Meet the Faces that You Meet by valtyr:
Identity porn. AU post Cap’s death in ways that should be pretty obvious.

(Don’t let the Bucky/Tony tag turn you off, it is NOT Bucky/Tony at all).

Missing in Action (the Who Are You Underneath Remix) by navaan:
Tony and his friends are on a mission in war torn Europe and Fury has
sent along a soldier to serve as their driver and a sort of attache.
Tony likes him well enough, but the real help he’s counting on is that
of Captain America, especially with Hydra hot on his trail. But then
Private Steve Rogers has a mishap that costs him his memory – and Tony
can’t seem to make contact with Captain America at all.

I Don’t Want My Heart to Show by @laudatenium​:
On a gut impulse, Tony Stark hires Steve Rogers to be
his bodyguard after Steve rescues him from an automotive crash.  But
despite his resolution not to share his secret with Steve, the man is
far different than anyone else Tony’s ever known.And thus it
begins.——AU of Tales of Suspense 45, where Steve was melted before
the Avengers existed.  And the fallout.

I Said “I Love You,” What Does It Matter If I Lie to You? by @lelantusposts​: 18 year old Tony Stark is your typical teenager. Well,
except for how he’s the playboy billionaire heir to Stark Industries and
working on two PhDs. Oh, and 6 months ago he was kidnapped by – well,
no one really knows who. Since his rescue (excuse you, Tony liberated
himself), he’s also been keeping a pretty big secret. Here’s a hint:
it’s shiny, red and gold, and flies. Tony’s had a productive couple of
months, but the fact that his grandfather keeps trying to hire
bodyguards for his “safety” is really putting a cramp in his ability to
keep his secret superhero identity, well, a secret.Steve Rogers
wakes up in 2015 and finds out that he’s missed 70 years (Oh god, does
this mean he’s 94?), a revelation that he handles with much less grace
than usual. Mostly, Steve just wants to be Captain America again, but on
his own terms and without a lot of fanfare. To fill the time while
Steve tries to figure out the best way to resurrect a dead superhero,
his good friend Isaac Stark offers him a job: bodyguard to Isaac’s
grandson, Tony Stark – who seems to get into a surprising amount of
trouble for a teenager. “There’s no better introduction to the 21st
century than through Tony,” says Isaac. Somehow, Steve is not reassured.

Straight On Till Morning by @sineala​: Tony Stark resigned his commission in Starfleet five
years ago, after a disastrous away mission, and he swore he’d never go
back. He just wants to be left alone to build warp engines in peace. But
the universe has more in store for him than that, as he discovers when
Admiral Fury comes to him with an offer he could never have expected and
cannot possibly refuse: first officer and chief engineer aboard the
all-new USS Avenger, a starship of Tony’s own design. What’s more, the
Avenger’s captain is Steve Rogers, hero of the Earth-Romulan War.
Believed dead for over a century, Steve is miraculously alive… and
very, very attractive. But nothing is ever easy for Tony. As he wrestles with his secret
desire for his new captain and his not-so-dormant fears, another mission
starts to go wrong, and Tony becomes aware that Steve has secrets of
his own – and the truth could change everything.

Prisoner’s Dilemma by @awesomeavocadolove​:
After taking the airplane down in the Arctic, Steve wakes to find
himself imprisoned as a human test subject. With no idea where in the
world he is, his only ally is a fast-talking inventor in the cell next
door. Something’s off about Tony that Steve can’t put his finger on, and
it’s obvious Tony doesn’t fully trust him either. But to escape they
may not have a choice…

And a couple of my own, since I love this trope:

Celestial Navigation by sabrecmc:
18 year old Omega!Tony finds himself Bonded to Captain Steve Rogers.  He isn’t happy about it until he is.

A Funny Thing Happened on the Way to Oblivion by sabrecmc:
“Mr….Mr. Stark?” the man asked, shaking his head as if to clear it, grip
convulsing spasmodically on Tony’s hand.“That’s
me,” Tony responded gruffly.  Of course the man recognized him.  His
face had been everywhere before the whole Iron Man thing and now…well,
now…so yeah, totally understandable.  Guy was probably thinking of his
lawyer’s speed dial number.  “Look, ambulance is on its way, okay, so
just sit tight.  You’re going to be fine.” “I—I think I missed my date,”
the blond man said.  And promptly passed out. Or, how Tony accidentally
kidnapped Captain America and then wanted to keep him.