This paper describes an improved RP-VSELP (IRP-VSELP) speech coding. The RP-VSELP is classifed as a fast VSELP since it produces a comparable speech quality to the VSELP with much simplified system complexity. The new RP-VSELP coder proposed in this paper has additional new features, such as a fast codebook search obtained by employing backward filtering and pitch-adaptive regular pulse excitation. Due to new features added to the original RP-VSELP, the proposed method not only reduces the complexity of the original RP- VSELP but also provides an improved speech quality. Throughout objective and subjective tests, IRP-VSELP outperformed RP-VSELP as the ref erence coder. Simulation results are presented to verify the performance of the proposed method.