In this paper, we argue that because of recent advance of network & CPU technologies, workstation clusters are poised to become the primary parallel computing infrastructure for science and engineering computing. After analyzing and comparing the communication performance of three popular networks: 10Mbps Ethernet, 100Mbps Ethernet and 640Mbps Myrinet on an experimental workstation cluster, we point out that two main factors hinder the wider application of workstation cluster: low efficiency of communication system (both hardware and software) and lack of friendly parallel program development environment with accessory tools. For these two problem, we implemented two workstation cluster systems for different performance/price rate requirements: one is 8 PowerPCs with shared media network, another is 8 Sun Sparcstations with switch network. By using Reduced Communication Protocol ( RCP ), we dramatically improved the performance of communication system; by expanding the language support of PVM and adding several useful tools, we build a visual integrated parallel program development environment IPCE. On our platform, we also analyzed several massive applications, such as GRI benchmark, earthquake simulator, weather forecasting and some NAS benchmarks, and we get very good results for these coarse-grain to middle-grain applications. The speedup ranges from 5.83 to 7.98 and parallel efficiency reaches to 72.88%~99.7%.