Saints coach Nathan Brown said: “Luke is an exciting addition to the squad. He is a good organiser and possesses a great kicking game too.
“We are always looking to improve the team and I’m sure Luke will contribute to that. We are looking forward to having him on board.
“We would also like to thank Penrith Panthers for allowing Luke to be released from his contract to join us next season.”
Walsh is expected to be the first of many to sign at Langtree Park for 2014 after St Helens‘ injury-hit 2013 season.