Steve McNulty joins the Minstermen after just last month winning promotion to League One with Tranmere Rovers.
It's been a busy summer so far for Steve Watson and York City - this their sixth new signing so far.
With the new season just around the corner, 35-year-old McNulty will add bags of experience with over 600 appearances through a career spanning over 15-years.
"I like his leadership skills and the way he plays football," Watson told the club's website.
"He's an absolute leader at the back which is what every club needs. His record speaks for itself and his credentials are fantastic.
"That's pretty much the icing on the cake of the squad now and I am really happy with what we are going to start with on Monday."