The 33-year-old midfielder arrives on a free transfer and joins fellow new boys Jack Hobbs and Dele Adebola at the KC Stadium.
McKenna admits he is relishing a fresh challenge with The Tigers after agreeing terms on a deal that will keep him with Hull until 2013.
"This is a great opportunity for me to make a new start at a massive club," said McKenna. "I've played against Hull City in the past and I know that the stadium and support here is absolutely fantastic.
"I know the manager and his staff and when I sat down and spoke with them I knew straight away that this was where I wanted to come.
"Now I just can't wait to get my teeth into pre-season as I'm really excited about the coming season with this club."