Control room operators face working conditions characterized by prolonged sitting postures, high visual workload, and significant time pressure while monitoring systems. Inappropriate chair design that does not meet anthropometric requirements, monitor positions that are too high or too low, and keyboards or mice placed too far from the operator can lead to physical discomfort. This study aims to analyze ergonomic risks among control room operators based on working postures and musculoskeletal complaints experienced during work activities.The research was conducted using an observational method with an ergonomic approach. Data were collected through interviews, completion of the Nordic Body Map (NBM) questionnaire, and direct observation of operators’ working postures, which were subsequently assessed using the Rapid Office Strain Assessment (ROSA) method. Operators’ physical characteristics, such as body height and body proportions, were obtained based on self-reported statements and used as supporting data in the analysis. The results based on the NBM questionnaire showed that 5 out of 6 operators were classified as having a low risk, while 1 operator was classified as having a moderate risk. However, the working posture assessment using the ROSA method indicated that all operators obtained scores greater than 5, suggesting that the working conditions are at an ergonomic risk level that requires corrective action. Further analysis revealed that the work chair was the workstation component contributing most significantly to the high ROSA scores, particularly in relation to seat height adjustment, backrest configuration, and body support during work activities. Based on these findings, improvements to work facilities are necessary, with priority given to adjusting work chairs in accordance with ergonomic principles. Such improvements are expected to reduce ergonomic risks, prevent musculoskeletal disorders, and enhance operator comfort and work productivity.