Evaluation method for one-dimensional assembly yield is presented based on Taguchi orthogonal experiment. Firstly,
according to Taguchi parameter design criteria, component loop sizes are taken for factors of Taguchi orthogonal
experiment, each factor is divided into three levels. After approriate orthogonal experiment table is selected, orthogonal
experiment is operated. Then the mean and standard deviation of close loop size are solved, which are used to obtain
assembly yield. The influence on assembly yield of each factor is analyzed by using extreme value method and the
results are validated by using Monte Carlo simulation. Finally, a gear components assembly is provided to illustrate the
effectiveness of the presented method .It has a guiding significance for machanical assembly design.