The performance of all-optical (AO) logic AND and OR gates, which are realized for the first time using reflective semiconductor optical amplifiers (RSOAs) as nonlinear elements, is theoretically investigated at 120  Gb  /  s. The switching modules that incorporate the RSOAs and exploit their potential for AO signal processing are the Mach–Zehnder interferometer and the delayed interferometer for the AND and OR operations, respectively. A performance comparison between an RSOA and a conventional semiconductor optical amplifier (SOA) is made by examining and assessing the quality factor against the operational critical parameters, including the effect of the amplified spontaneous emission. The obtained results confirm that these Boolean functions based on RSOAs can be executed at the target data rate with better performance than if conventional SOAs were used instead.