This chapter studies the influence of spatial diversity on the synchronization of MIMO-OFDM systems. Upon revising the main features of OFDM and diversity techniques, this chapter focuses on the following topics. First, the sensitivity of the MIMO-OFDM receivers to the residual synchronization errors is examined. Then the effects of spatial diversity on symbol timing and carrier frequency synchronization are investigated. Computer simulation results show that by exploiting the spatial diversity in MIMO-OFDM systems, the synchronization performance can be significantly improved.