Sweden international Larsson, 32, one of several high profile names to depart Sunderland in June, has put pen to paper on a one-year deal.
“I’m delighted to be here and I am really looking forward to this fresh challenge,” Larsson told Tigers TV.
“I had some options to consider, but I felt this was the best move for me to make and I can’t wait to get started now.”
Larsson, who started out in England at Arsenal, spent six years at Sunderland after joining in 2011 from Birmingham.
He has made over 500 appearances in English football and has 90 caps for Sweden.
Hull have now made six summer signings under head coach Leonid Slutsky following the arrivals of Ola Aina, Fraizer Campbell, Kevin Stewart, Ondrej Mazuch and Michael Hector.