This research was about analysis of mental and physical work load for all operators in PT. Barlow Tyrie Indonesia. The method used for mental burden calculation was NASA-TLX method. Physical work load calculation used Cardiovasculair Load percentage methods. The benefits of the research was PT.Barlow Tyrie Indonesia can maximize the operators productivity they could work that suited the acceptable load. From the calculation of mental work load, the weight workload (WWL) score was 80 and belonged to”High” category. Then, from the calculation of physical work load, the calculation of job exhaustion level had been done, and the result of Cardiovasculair Load percentage (% CVL) was 41 %. From those results, it was known that the job did not cause fatigue. The improvement had been done, the result of physical workload is about Cardiovasulair Load which is accepted by MFU operator become 21%, while mental workload was the result of NASA-Task Load Index which is accepted by MFU operators become 34 it belonged to “low”