"Since My Food Bag's IPO 15 months ago, Mr Marshall has been working closely with the other directors to transition the company to a best practice, public market structure," the company said.
"That work is now largely complete, and the company has continued to deliver on the targets set out in its Product Disclosure Statement provided at the time of the IPO.
"As such, Mr Marshall has indicated that he considers this an appropriate time to step back from his position on the board," the company said.
"As a director of funds which remain one of My Food Bag's largest shareholders, Marshall continues to be a strong supporter of the business and has every confidence in its prospects."
The My Food Bag board said it would start a process to find a replacement.