A RISC-based multiprocessor system called MIEP (Multiple Inference Engine for Prolog) is proposed as a tool to construct an intelligent workstation for AI applications. The MIEP contains general purpose processor modules (processor with local memory) and PIER (a Prolog inference engine on a RISC) modules interconnected by a bus. A PIER module contains a LISCP (limited instruction set computer for Prolog) as the kernel Prolog processor, a floating point coprocessor, FPC, and a cache memory. The PIER module has been simulated and evaluated with some benchmark programs. Primary results show that PIER can achieve a peak performance of more than 500 KLIPS. In addition, a parallel execution model for Prolog on MIEP has been studied and evaluated. Design issues and features of the MIEP system are presented.