Abstract: Thirty-three kinds of blood proteins and isoenzymes encoded by 37 genetic loci in Wenshan and Diqing yellow cattle from Yunnan Province were analyzed by horizontal starch gel electrophoresis,of which 6 genetic loci display polymorphic pattern.In the representive populations of Wenshan yellow cattle,the percentage of polymorphic loci(P) is 0.1389,the mean heterozygosity (H) is 0.0610.As for Diqing yellow cattle population,P=0.1667,HS=0.0711.We generated Neis genetic distance matrix for 10 cattle breeds based on our results as well as the data reported previously.The relationships among the 10 cattle breeds were analyzed by "UPGMA","CONTML" and "NEIGHBOR"methods (PHYLIP 3.5C).Our results showed that Wenshan yellow cattle seemed to be mainly Bos indicus origin and Diqing yellow cattle mainly contained Bos taurus blood.In addition,our results also implied that Yunnan yellow cattle might be of a mixture of different populations.Some populations were domesticated by local people and the others came from outside.This resulted in a high level of genetic diversity.