This article applies the method of formulating those test projects affecting product system properties into a matrix with tabular units. According to the complexity of product system, the complexity in test operation, economical cost for a test, etc., the paper proposes the concept of whole matrix unit, intersection matrix unit and particular matrix unit test plan to test the product properties. The result indicates that there are various complicated factors influencing the properties of the product, aggravating the unstability of products system in operation. By utilizing the unit test matrix method, we can obtain experimental data chain for advancing the product reliability design, optimizing product systematical structure. With the existing scientific and technical results, together with the experiment data analysis, mean value and strategy of reliability design, we can promote product reliability and robustness.