PT SAI APPAREL INDUSTRI Semarang is a clothing company which manufactures export production with cut-bray denims in particular. During the production process, it is currently happened the accumulation of work-in-progress products that cause bottle neck in one of workstations, while idle time in another workstations.. The problem among the workstations is known as the assembly line balancing problem. The consequences of this situation, least working efficiency phase and critical product capacity occur; therefore unjUllilled production target and demand in time take place. According to production capacity calculation, noticed numerous workstations have been through bottle neck such as press-waistbands workstation, thus line balancing is necessary. There are three methods of line balancing including Ranked Positional Weight (RPW), Kilbridge Ang Wester s Method and Largest Candidate Rule (LCR).