Young was one of several current and former politicians being looked at for the appointment, which will be made by Gov. Charlie Crist (R).
Young has served in the House for nearly 40 years and has been considered a potential retiree. His decision to remain in the House appears to provide a strong indication that he will seek reelection in 2010, which could be his toughest reelection race in years.
Democrats have recruited state Sen. Charlie Justice (D) to run against Young, with the hope being that he might consider retiring in his battleground Tampa-area district.
The appointment would have served a similar function for the Democrats, given that Young would have been yielding his seat for it.
Young is the second current House member to decline Crist's interest in a potential appointment, joining Rep. Lincoln Diaz-Balart (R-Fla.).
The current list of those being actively considered by Crist is as follows:
Former Rep. Mike Bilirakis
Former Rep. Clay Shaw
Former Rep. Lou Frey
State Rep. Jennifer Carroll
North Florida University President John Delaney
Former U.S. Attorney Bobby Martinez
Former Crist Chief of Staff George LeMieux
Former state Sen. Dan Webster
Former Florida Secretary of State Jim Smith