Marino retired after the 1999 season, ending a 17-year career as the most prolific quarterback in NFL history, and had been working as an analyst for HBO and CBS.
Soon after taking his first front office position, it became clear Marino would have to make too many lifestyle changes to fill the job.
"I knew it would involve a significant lifestyle change, but after further reflection, it became clear that those adjustments were ones that my family and I are not prepared to make at this time," Marino said.
Dolphins owner Wayne Huizenga said he was disappointed in Marino's decision, because he thought the former quarterback would make "an outstanding football executive."
Marino is the NFL's all-time leader with 61,361 passing yards, 420 touchdowns and 4,967 completions in 17 years.