Christian Aid has paid tribute to all of those who face significant dangers as they help locals caught up in the crisis that has engulfed the young nation.
It was speaking after the United Nations World Humanitarian Day, which aimed to draw attention to the risks people take on a daily basis to deliver aid during conflict, emergencies and disasters.
The charity also wants 25% of global aid funds to go directly to local organisations, who are often on the front line of relief efforts.
It says humanitarian personnel in South Sudan operate in a climate of conflict, chronic poverty, economic crisis, severe food shortages and weakened infrastructure.
Almost 60 aid workers have been killed there since the conflict began in December 2013.
Violence flared again after South Sudan celebrated five years of independence in July.
In June 2016, a staff member from one of Christian Aid's local partner organisations was shot and killed when civilians were attacked in the town of Wau.
Rosie Crowther, Christian Aid's emergency programme officer for South Sudan, said: "The humanitarian situation in South Sudan has deteriorated rapidly in recent months.
"As the scale of need continue to escalate, so do the challenges facing humanitarian workers - both South Sudanese nationals and those from overseas.
"Over the years, our local partners have responded courageously, working in remote, hard-to-reach areas, and staying with communities even when other agencies have pulled out due to security issues.
"In some situations our partners have even moved with displaced local populations, so that they can continue to provide assistance.
"The cost of this work is incredibly high: aid workers have been harassed and attacked in South Sudan.
"Tragically, one of our partner organisations recently lost a staff member, who was killed in the town of Wau.
"During last month's clashes, some of our partners had their compounds looted and facilities destroyed, while some of our staff and partners were forced to abandon their homes amid the fighting - many sought refuge in church compounds."
Millions of people around the world rely on aid workers to help them access shelter and food.
