The thesis used RAPD molecule marker to estimate the genetic diversity of seed orchard of Pinus tabulaeformis.The results showed that 11 random primers produced 95 loci in total,77 of which were polymorphic loci,the percentage was 81.05%.The genetic background complexity and diversity of seed orchard of Pinus tabulaeformis were shown clearly.Nei's genetic diversity analysis showed the efficiency number of alleles was 0.3881 and Shannon's information index was 0.5678 on average.Largely contrast were in Nei's genetic diversity and Shannon's information index,clustering analyses result indicated the genetic relationship was comparatively close and the genetic background was narrow,Genetic variation displayed the special disproportion in genome