This study evaluated the postures that workers used to perform 18 different tasks at an electric iron assembly plant by classifying the common simultaneous and individual postures of eight upper body segments and the fingers. The postures of the head, upper arms, lower arms, hand, and trunk were assigned to the categories of “Neutral,” “Bend,” “Twist,” and “Invisible.” The finger postures were also assigned to 14 categories. Overall, most workers bent the head, lower arms, and hands and used power grips to wrap all fingers around parts and tools. The upper arms and trunk were in neutral positions because the workers stood at a conveyor belt. Among 18 tasks, the task of “setting temperature” seemed the lightest work because most body segments were in neutral positions for more than 54.6% of a cycle time, while the task of “palletizing” seemed the most stressful work because all body segments were bent more than 54.4% of a cycle time. These posture differences among the tasks result from the different task characteristics of workplace design, task difficulty, and work duration. It would be useful in designing workplace and evaluating physical workload. © 2012 Wiley Periodicals, Inc.