The firm of Copeland, Cook, Taylor and Bush plans to make the announcement on Thursday. A former Musgrove employee confirmed he's taking the job.
The former governor, 47, left office in January and has been teaching classes at the University of Mississippi in Oxford. He lives in Madison County.
Musgrove is a Democrat and was defeated by Republican Haley Barbour last November.
Musgrove also served one term as lieutenant governor and two terms in the state Senate from Batesville.