The press campaign, to appear in national titles including The Times and The Guardian later this month, appears with headlines such as "Fruitstock '05. Same place, same time, new flip flops".
It will be supported by a new website at fruitstock.com with details on the event, organisers and acts.
The festival, now in its third year, will be held on August 6-7 in Regent's Park in London.
Acts lined up include over the two-day event include Radio 1 DJ Gilles Peterson, Jazz FM DJ Campbell Burnap and the only act to play live every day in Glastonbury, Jerry Fish and the Mudbug Club.
Last year, Fruitstock attracted 100,000 people, but with increased publicity Innocent is expecting around 125,000 this year.
Seperately, Innocent Smoothies is launching its first nationwide television campaign focusing on the one-litre, take-home smoothie cartons.
The ads, created in-house will run throughout July and feature chickens in a park.
Richard Reed, co-founder of Innocent, said: "The ad reflects the values of the company, fruit first.
"It just wouldn't feel Innocent to hire big-name celebrities to endorse our drinks. We are proud of what we have achieved with just a few guys and a chicken in a park with a camera."
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