[Mental Workload Analysis using NASA TLX Method in Logistic Department of PT ABC]. Every worker in company has different task, and each work will produce its own workload. The workload is a term used to refer to the price or cost of achievement of a target activity. PT ABC is a company that manufactures mobile phones. The high demand every day, make the workers in the logistics department can not complete their work according to the schedule, so the workers have to work overtime to complete their work. Frequent overtime have impact on workers, both physically and mentally. The high level of mental workload will cause mental fatigue, accompanied by the emergence of feeling tired, fatigue, lethargy, and decreased alertness. To determine the level of mental workload of employees at the logistics department, measurements using NASA TLX (National Aeronautics and Space Administration Task Load Index) had been held. This method measures 6 dimensions of the workload which are Mental Demand, Physical Demand, Temporal Demand, Performance, Effort and frustation Level. Based on the score obtained, it is known that 38.10% of employees have a high mental workload, 57.14% had moderate mental workload, and 4.76% had mild mental workload. To reduce the level of mental workload, company could increase the number of workers especially helper and scanner, which has the highest mental workload