Using the method of multiloci electrophoresis, genetic co-adaptability of Hu Sheep was analyzed according to allele frequencies in 14 structural loci. The results showed that no co-adaptability existed in the dominance-dominance model, while co-adaptability was observed in X-p–Cat combination locus of dominance-codominance model and in Po–CA, Po–Cat combination locus of codominance-codominance model. The findings demonstrated that co-adaptability occurred among neutral structural loci and played a key role in maintaining genetic situation, equilibrium or disequilibrium.