Abstract: 【Objective】Paeonia ostii ‘Feng Dan’ is a special peony variety for producing seeds and processing edible peony seed oil. It combines medicinal and health care value and has strong economic value. The author conducts a breeding research focus on yield and combining oil quality to initially screen out suitable individuals for further cultivation.【Method】We used 6-year-old ‘Feng Dan’ seedlings planted in Luhe, Nanjing, China, as experimental materials. In total, the 31 individuals with high, medium and low yields per individual were chosen from preliminarily selected plants. The seed oil content of each individual was determined by nuclear magnetic resonance, and the main unsaturated fatty acid(α-linolenic acid)content in the seeds of each individual was determined by gas chromatography/mass spectrometry(GC-MS). 【Result】The average seed per individual was 47.57 g. The greatest and lowest yields were obtained from individual No.1 at 98.89 g and from individual No.31 at 25.73 g, respectively. The average oil content was 29.41%. The oil content of No. 10, 19, 20, 24, 26 and 28 were greater than 30%, while that of No.12 was only 23.59%. The average α-linolenic acid content was 34.89%. The α-linolenic acid content of No.11 and 13 were greater than 40%, while that of No.21 was only 28.55%. Using the subordinate functional value method and cluster analysis, the 31 ‘Feng Dan’ individuals were classified into three categories. Seven individuals with good comprehensive performance levels in Category I can be selected for further observation and the cultivation of high-quality individuals. In Category II, individuals with one or two desirable traits could be used as reserve materials for future cross breeding.【Conclusion】The coefficient of variation for yield per plant of oil tree peony is larger, and the difference in seed setting quantity among individual plants is larger, while the coefficient of variation of two indexes of α-linolenic acid content and oil content is relatively small, and the two characters are relatively stable.