The requirements for facilitating spectral efficiency and energy efficiency become increasing important for future wireless networks. Ambient backscatter communication (AmBC) has recently been recognized as a technology to meet these requirements. Furthermore, reconfigurable intelligent surfaces (RISs) have recently emerged as an effective technology to ameliorate the performance of wireless communications. Motivated by these, this letter investigates the channel characterization and the performance of the RIS-assisted AmBC system. Particularly, we derive the closed-form expressions of the outage probability (OP) and average symbol error rate (ASER) of the considered system. To gain insight into the systems, the asymptotic OP and diversity order are obtained too. Monte Carlo simulations are employed to verify our obtained analytical result. Our findings unveil that the performance of the RIS-assisted AmBC systems is significantly better than that of the conventional AmBC system.