Abstract: This paper discusses the application principle of the GJB 150A and shows how to tailor it to deal with its restrictions, and the tailoring includes the tailoring of the test methods, the tailoring of the test procedures, the tailoring of the test sequences, the tailoring of the test conditions and the tailoring of the test steps. Four important tailoring factors on the basis of laboratory environmental test types are the tailoring foundation, the tailoring methods, the tailoring time and the persons to do the tailoring and to take the responsibility. Finally, it is pointed out that tailoring is determined by the general development requirements and the environmental worthiness requirements of the products. In different development phases, the test procedures and the test conditions in the environmental test should be tailored by indexes of the environmental worthiness requirement.