Abstract: A fixed sample plot of 50 m×100 m was established in natural coniferous and broad-leaved mixed forest in Fengyangshan National Nature Reserve, Zhejiang province.Tally was carried out on plants with DBH ≥5 cm and height ≥ 2m in the plot.The result demonstrated that there were 1952 plants, belonging to 63 species of 23 genera and 22 families.Structural parameters of the top 10 dominant tree species were analyzed by Winkelmass, especially on bivariate distribution structural of Pinus taiwanensis and Schima superba in this plot.Results showed that the dominant species were aggregated distribution and had a high mingling degree, except S.superba was random distribution.The bivariate distribution characters of P.taiwanensis and S.superba had a similar frequency, random distribution at the same level of dominance or at the same mingling degree.DBH had not difference in low mingling, but in extremely intensity mixed was significant.It concluded that special structure of the plot was complex and diverse, indicating stable community structure and normal succession.