Abstract: A Symbolic Interactive Debugger（SID）of the Galaxy-Ⅱ Super Machine（GSM-Ⅱ）is described briefly in this paper,including the environment,functions and characteristics of the SID design ideas,and implementation techniques of the SID are also presented.GSM-Ⅱ is a very complicated parallel machine with up to 4 CPUs running simultaneously,providing a 1,1000 MFLOPS capability.The complexity of the GSM-Ⅱ imposes great difficulties on the design and implementation of the SID.