The synchronizability of mobile Ad Hoc networks is investigated in this paper. The synchronizability is measured by eigenratio R. A smaller value of eigenratio R leads to a better synchronizability. The results indicate that with the increase of clustering coefficient C, eigenratio R increases in interval, but with the process going on, eigenratio R decreases. The eigenratio varies with clustering coefficient reither in direct proportion nor in inverse proportion, but rises first and reduces later,so there aooears a clear maximum value in between.