Abstract: The test of distinctness, uniformity and stability (DUS) of new plant varieties was the foundation for new varieties protection. DUS test guideline of Phalaenopsis was researched in order to adapt to the development of our Phalaenopsis and need to be in line with international standards. There were 78 characters and 22 standard varieties in DUS test guideline. The principle of test guideline, construction of character table, selection of standard varieties and assessment of DUS were described in this paper.