Steven Tyler's had a birthday surprise!

Steven Tyler was 'surprised' by his birthday celebrations.

The Aerosmith rocker turned 66 years old on March 26! He received an award at the National Music Publishers' Association Celebration of the American Songwriters in Washington D.C., on Tuesday.

And, of course, he was also presented with a special cake.

"Steven was really surprised", a source told People magazine of the rock star's reaction when he saw his face painted in frosting on the piano shaped dessert. "He was not expecting it".

The star then performed several hits for all attenders of the party.

Democratic representative John Conyers of Michigan joined Steven onstage during the performance of song Walk This Way. The musician showed the politician some dance moves.

"Steven was teaching him how to walk this way", an onlooker revealed.

The star isn't bothered at all about getting older, as turning 66 isn't significant for him.

"For Steven, age is just a number. He doesn't think about his age", a friend told the publication.

The rocker believes people should not dismiss the idea they are being spied on.

"Yeah, I have. I always thought that once they invented credit cards and so forth, that there was a whole hidden agenda. You can either be naïve and not think so, or you can smarten up and know that there is", he explained to The Cut.

"And once there's a thing called the Internet, of course it can get tapped into. It just can. I always knew it could, so."