Simplification of consonant clusters is one of the most challenging opacities in English phonological changes. The past LP analyzed this opacity with the derivations of the rules. But this paper analyzes this opacity with Lee’s(2009) markedness oriented candidate chains(M-CC) and precedence constraint. It is the revision of McCarthy’s(2006a, 2007) OT-CC(faithfulness oriented candidate chains and precedence constraint). In this paper I will show the derivational effect without derivational processes in the simplification of consonant clusters.