The purpose of this paper is to compare the characteristics of operator behavior in a conventional and an advanced MCR (Main Control Room) under a simulated emergency and to describe different operation characteristics and common operation characteristics of operators in the analog and digital environments. To this purpose, we compared the operation characteristics from a task point of view including ‘checking/verifying process parameters’, ‘component manipulation with device control’ and ‘operation by operator’s knowledge’. Based on the results, in an advanced MCR, opportunities to successfully cope with a given scenario have increased due to design characteristics of digital environment and operator’s simultaneous cross checking.