| PT. INP is a plastics industry company. The problems that occurred in PT. INP is the turnover rate> 9.1%, the percentage of employee absenteeism> 4%, and 40% of employees complain of mental workload. This problem is expected to affect the performance of employees. It can be seen from the data on production and order data that has not reached the target. The purpose of this study is to measure mental workload using the NASA-TLX, the measurement of job satisfaction by using MSQ, in addition to determine the effect of mental work load on job satisfaction and employee performance using simple regression, as well as determine the effect of mediation using path analysis and Sobel test. The data collection is done by census method to 191 respondents. Based on the results of data processing, it was found that the measurement of mental workload to 191 employees give an average value of 58.39 weighted workload, which in the marketing department and the warehouse have a high mental workload, so the recruitment process is needed. Job satisfaction measurement results obtained at 3.37 categorized quite satisfied with this aspect of the perceived need to be increased recognition by all employees, so the company must give compliments and appreciation to employees. Hypothesis testing gives results that the mental workload gives a significant effect on job satisfaction, mental work load significantly influence employee performance, job satisfaction have a significant effect on the performance of employees, and the influence of mental workload on employee performance is mediated by job satisfaction. |