Robertson who set up the company, one of the UK’s most high-profile tech success stories in 2000, has told the board he wants to step down from the top job but remain on as a non-executive director, according to Sky News which first reported the story.
Robertson will keep a sizeable stake in the fashion e-tailer worth hundreds of millions of pounds.
His departure comes after a tough couple of years at the firm, which has issued several profit warnings and had a fire at its distribution warehouse in Barnsley.
Robertson also sold £20m of shares in January - which suggested he may have been considering stepping down. He still has shares worth around 8.39 per cent of the total issued share capital.
Current chief operating officer Nick Beighton is widely tipped to take the top job at the world’s second most visited fashion website and sources said a succession plan at the e-tailer had been well underway for some time.
Asos declined to comment on the leadership change.
Shares in Asos dipped yesterday to close down 0.33 per cent.