Abstract: his paper considers the scheduling of FMS job-shops, The use of simulation in the designand control of flexible manufacturing Systems has proven to be more practical than traditional mathematicalapproaches. Although simulation-based scheduling has shown advantages in capturing the scope,complexityand dynamics of the job-shops production, it leaves the user with numerous work of generating, testing,andselecting different control:trategies. In this paper. a discrete-event simulation-based boftware Faetory Simulation Scheduling Environment (FASE) is outlined. A new simulation architecture,based on decision rule-base, is suggested. Also detailed is its design and implementation in the FASE system.