A press release by Save the Children is warning of nearly half of the country population facing hunger.
The statement states the country is facing the highest proportion of food insecure people in the last ten years.
Country Director Deidre Keogh, says malnourished children have substantially reduced immune systems and are at least three times more likely to contract and die from diseases like cholera and pneumonia than healthy children.
He adds that without urgent funding to increase and maintain humanitarian services, many children are in danger of dying.
According to the organization more than six million people currently need urgent food assistance, including more than one million children.
It points out that areas of continuing conflict like Jonglei, Upper Nile, Western Bahr El Ghazal, and Unity show the highest levels of food insecurity.
The agency says about two hundred and seventy thousand children in South Sudan are severely malnourished and at risk of starvation.
Save the Children calls on access to children in need to be guaranteed, humanitarian assistance to be enhanced and sustained, and for a lasting end to the conflict.