The 34-year-old front-rower is in his second season with the Vikings after previous brief spells in Super League with Leeds and Wigan but has been badly hit by injury.
"I was really keen to play on in 2014 but, having picked up a hamstring injury in the early part of the season, as luck would have it I then did my knee in my first game back," Cross said. "It was then when I thought 'enough's enough'."
He added: "I can come back from a minor injury but if it was anything more serious, I genuinely don't think that I've got the drive left in me to keep coming back from injury after injury.
"I'm really comfortable with the decision I've made and it's good to finally get it out in the open."
Cross, who played for Canberra, Melbourne and Newcastle and represented New South Wales before coming to England, intends to go into coaching in Australia and has not ruled out returning to work in Super League.
"I have a genuine desire to be a career coach and, looking further down the track, only a fool would not put in an application for a position that suited them, either in Australia or in England," he said.
"I'd love nothing more than to return to this country one day in the future and take up a head coach position. If Widnes came knocking, I'd be over here on the next flight, for sure."