Abstract: The selection method and standard of the superior seedlings were studied and based on the datum with 3 to 5 years old Paeonia ostii,and according to the standard to select the appropriate plants to establish Paeonia ostii superior seedling nursery base,aiming to provide excellent germplasm resources for large-scale cultivation of Paeonia ostii.The results showed that:①heights and basal diameter increments among 3~5 years old Paeonia ostii were significantly different,and difference in basal diameter growth was more than in the height of 3 and 5 years old seedlings.②Height and basal diameter increment of individuals among the same age were in positive correlation,but only those of 5 years old seedlings were significant.③The average height and average basal diameter adding one point five times by standard variance selection way were used as the Paeonia ostii superior seedlings selection standard,and the 3 years old seedling selected ratio was 3.81%,4 years old seedling selected ratio was 4.57%,5 years old seedlings celeated rotion was 4.36%.④955 superior seedlings were selected by comprehensive selection way with a selection ratio of 3.91%.