Real are currently under the guidance of Manuel Pellegrini, but the Chilean has struggled to win over a sceptical Madrid support.
"Could he (Benitez) take charge of Madrid? Why not?" Salgado told The Sun. "The opinion on Rafa in Spain is great.
"He won the league twice with Valencia and got them to two Champions League finals.
"First let's see if Real can win La Liga. I think, though, it will be a big battle between Benitez and Mourinho."