The 25-year-old was allowed to leave beaten League Two play-off finalists Wycombe at the end of his only campaign with Gareth Ainsworth’s men, making 47 appearances for the Chairboys over the course of the season.
Murphy scored a stoppage-time winner against his new club for Stanley in 2013 and also netted in two other fixtures against Morecambe.
“We know all about Peter and what he is capable of,” boss Jim Bentley told his club’s official website.
“He is an experienced midfielder who plays with passion and aggression and is exactly the type of player we need.
“We all know we haven’t scored enough goals from midfield over the past couple of seasons and Peter is a player who will add that to the squad. He has scored 16 goals in the last two seasons and we hope he can continue that type of form here.
“I am delighted that we have got him and I’m sure he will be a real favourite with the fans.”
Murphy fell down the pecking order at Wycombe and admitted he was keen on finding regular first-team football again.
“I just want to play regular football and I wasn’t getting that at Wycombe at the end of last season,” he added.
“I was allowed to talk to other clubs and when I met Jim and Kenny (McKenna, assistant manager) they were brilliant with me. They have got a real ambition and really sold their vision to me.
“I’m just someone who wants to play football regularly and hopefully I can do that here and help Morecambe get success.
“I know some of the lads already and know that there is a good squad here and I’m really looking forward to next season.”