This industrial research was studied an improvement of efficiency in natural fiber production plant. The objective was improvement process by using IE techniques which this method was once green technology for industrial problems solving. Now process had build-up in process (WIP) due to unbalance times between trimming station and visual inspection of station. Therefore the research studied work of staffs; time study and data analysis through 5W1H were used for analysis of WIP root cause. The cause of problems founded were the transportation loss of between section had over necessity and loss of visual inspection for repair. Therefore it had bottleneck in process. Consequently the researchers applied ECRS in each working processed by separation of repair station. Repairs of items were isolated from the main flow path of the process. Calculating of work flow rate was used for identified operator for repair station. As a result of the above production improvement Times of visual inspection in a lot was decrease from 283.84 hrs to 160.19 hrs. It was decreased in 43.56%. In addition the effect of separation from the repair process made the total times of all process was decreased from 792.78 hrs/lot to 669.14 hrs/lot. It was decreased in 15.60% and decreased work in process had from 17 lots/day to no work in process.