The Hollywood heartthrob - who is married to Blake Lively - is nervous when he meets a girlfriend's father for the first time, but says the fact he is a really nice guy always wins them over.
Ryan - who was once engaged to Alanis Morissette and was married to Scarlett Johansson - said: "I had a girlfriend when I was 18 until 22 and I remember being terrified of meeting her dad. I'd heard he was pretty hard, but actually it was fine.
"You always have to have a he amount of respect for the father of a girl you're dating, but I like to think I'm the guy the parents actually like."
Asked what his top tip for charming parents is, Ryan, 36, claims it is convincing them he isn't in a rush to marry their daughter and take her away from them.
The 'Safe House' star - who tied the knot with Blake in a surprise ceremony in South Carolina just one year after they met - said: "You have to let him (the father) know you respect his daughter and that you're not going to drive off with her and elope. You want to make sure he knows she's in good hands.
"I'm fine at that, I think. I'm a pretty nice guy."
The A-list couple walked down the aisle in an intimate family-filled ceremony which took place in a barn decorated with flowers and candles, as Blake wanted a "rustic" vibe for her big day.
However, Ryan isn't in any rush to repeat the experience of their romantic big day any time soon.
Speaking to the new issue of LOOK magazine, he laughed: "Funnily enough, I haven't been camping since that experience [the wedding] so I can't see it happening soon, but I'd love to one day."