ABSTRACT Some limitations, such as rating and timing, are encountered in the traditional time study of stopwatch. Applying the theory of learning curve can deal with the above questions and quickly obtain the normal time of a task. For performing a certain task, the learning effect of an operator which can be affected by gender and motion classifications will be discussed in order to establish the standard time of a task. Therefore, an experiment and analyses of variance for the two factors, the classifications of motions and gender, upon the learning effect of an operator are conducted. According to the results, gender and motion classifications affect the learning effect of an operator and interact with each other upon the learning effect. Based on the consequence, the tasks can be assigned appropriately to an operator on the line so as to promptly establish the standard time of them.