A statement on Soderling's website said Norman "wants to put more focus on his personal life and new projects".
"I've had the two best years of my career so far with Magnus as a coach," said Soderling, who will name a successor in the coming days.
Norman added: "I look back on a fun and fantastic 26-month-long period of time together with Robin.
"I want to thank Robin for the faith he has had in me to take care of his career, a responsibility I have tried to manage in the best way possible."
Soderling was as high as fourth in the rankings only last week, before slipping back to fifth behind Andy Murray after the ATP World Tour Finals.
The Swede is the only man to have beaten world number one Rafael Nadal at the French Open after Soderling defeated the Spaniard in the fourth round in 2009 when he went on to reach the final before losing to Roger Federer.
This year Soderling beat the Swiss in this year's quarter-finals in Paris but lose to Nadal in the French Open final.