The Arsenal man has struggled to live up to the hype that surrounded him as a younger player.
The 26-year old scored a brace after coming on as a second half substitute in England’s 6-0 hammering of San Marino, and Redknapp feels it’s time the Arsenal man lived up to his potential.
"Theo needs to have a season of playing," he said.
"He doesn't get in the Arsenal team regularly. He really needs to have a big season and show us what he is capable of doing.
"He is a great talent, he is a great athlete, he has got fantastic pace, but he needs to play 20, 30 games on the spin now and have a real run at it,” he added.
Redknapp gave Walcott his debut at the age of 16 while in charge of Southampton and feels the England international is capable of playing through the middle, as the seemingly endless debate over his best position rumbles on.
The lightening quick attacker has made a solid start to the season this year, however, and Wenger now appears to favour him in a more central role.
With Danny Welbeck sidelined for several months - and a lack of alternatives to Giroud - Walcott will undoubtedly be called upon to feature in his favoured position in the coming weeks.
His well-taken goals against San Marino suggest a player who knows where the net is, and if he can avoid the injuries that have so plagued his Arsenal career to date – it could just be his biggest season yet.