Many children's foods still contain half the daily maximum limit of salt in a single serving, research shows.
The study has revealed that parents are also confused about which foods contain too much salt.
This week is Salt Awareness Week 2008, and the charity Consensus Action on Salt and Health (CASH) are calling on parents to check the label before buying salty food for their children.
CASH also want manufacturers to lower the salt content of children's foods and provide clear salt labelling to help parents make informed choices.
Four to six year olds should eat no more than 3g of salt a day, but research found that foods commonly eaten by these children had over 1g salt per serving.
"Keeping children's salt consumption below the recommended maximum limits is vital," said Professor Graham MacGregor, chairman of CASH.
"With everything we know about the dangers of eating too much salt, parents need as much information as possible about how much salt is contained in the foods they give to children, and food manufacturers need to do as much as they can to reduce the amount of salt they put in children's food."
Betty McBride, director of policy and communications for the British Heart Foundation, said: "This must be a red light moment for food manufacturers, let's get colour coded labels on food packs now.
"We know that traffic light labelling is key to making food choices easier for shoppers. It would also allow busy parents to tell at a glance whether food they select is low, medium or high in salt and help them make healthier food choices."