The heat shock protein 70 (HSP70) complete cDNAs were cloned from hybrid sturgeon（♀Huso huso×♂Acipenser schrencki） and Polyodon spathula.The results of the hybrid sturgeon and Polyodon spathula’s sequence showed that this nucleotide sequence of HSP70 gene has 96% and 98% identity with the Carassius auratus(GenBank No.DQ872648.1) sequence published by NCBI/GenBank.The full length cDNA (HSP70 cDNA) from hybrid sturgeon and Polyodon spathula were 382 bp and 334 bp long,respectively.Compared with other vertebrates’ amino acid sequence of HSP70 by DNAstar software,the sequence similarity was 86.2% between fish and mammals,and 86.8% between fish and amphibian,respectively.The sequence similarity was high among different fish species,and the average value was 93.8%,which shows a higher conservatism.Phylogenetic tree was constructed for 12 species based on HSP70 amino acid sequences using MP (maximum parsimony) method.Three major clusters were recognized:cluster one consisted of hybrid sturgeon,Polyodon spathula,Megalobrama amblycephala,Carassius auratus,Cyprinus carpio and Danio rerio(bootstrap 96); cluster two consisted of Oncorhynchus mykiss and Salmo salar(bootstrap 100); and cluster three consisted of Homo sapiensand Rattus norvegicus(bootstrap 89).