[Objective] Identify and analyze the yeast detected in yogurt, quickly analyze to find the source, control product quality and prevent product quality problems.[Method] The yeast from bulged yogurt was determined by Rose Bengal Agar.After isolation and purification, the isolated strain was verified by observation of bacterial colony and cellular morphology. It was identified by physiological and biochemical identification and ITS identification respectively.[Result] The isolated strains were a single strain, which was Meyerozyma guilliermondii.[Conclusion] This study provided theoretical guidance and reference direction for the analysis of contaminated strains of yogurt in production.