From June, it will raise the wholegrain levels in children's brands such as Cheerios, Cookie Crisp, Golden Grahams and Nesquik to up to 25%, while sugar levels will be reduced by 10%. These cereals currently contain minimal amounts of wholegrain, which is thought to bring health benefits.
A green banner with Nestle branding will be introduced to packs, showing levels of fat, calories, sugar and wholegrain in individual servings.
Packs will also carry full GDA (guideline daily amount) information.
Cereal Partners' initiative follows the recent pledge by rival Kellogg to reduce the amount of salt in its main brands. It is intended to offer healthier breakfast options to mothers concerned at increasing levels of obesity.
Dez Timmiss, Cereal Partners' marketing director, said the company had decided to revamp the range after its research showed that 90% of the UK eats less than the recommended three servings of wholegrain a day.
The overhaul will be supported by a marketing campaign including TV ads by McCann-Erickson. It will target mothers and explain how cereal can be part of a healthy diet.
Press, poster and radio advertising will help drive home the message that wholegrain is healthy.
Other Cereal Partners brands, including Shreddies and Shredded Wheat, already contain 100% wholegrain.