Abstract: 344 bp partial sequences of cox Ι gene were obtained from ten Cysticercus cellulosae isolates derived from several areas of Henan Province by RT-PCR. PCR products were cloned into pMD19-T vector and recombinant plasmids were sequenced. Nucleotide sequences of partial coxⅠgene were aligned using the ClustalX 1.81, MP and NJ trees were constructed using the software PAUP version 4.0, and ML tree was also constructed using PUZZLE version 5.2. Sequence homology analysis was performed using the software WDANSIST version 2.5 and the Megalign program of the software DNAStar version 5.0. Results indicated that there was no sequence difference among the coxⅠ gene partial sequences of ten Cysticercus cellulosae isolates, which belonging to Asian genotype. cox Ι partial sequence of Cysticercus cellulosae can be helpful to distinguish validly between Asian and American/African genetype, and can be used for differential diagnosis of different Taeniidae tapeworm. Therefore, cox Ι is expected to be a differential marker for PCR differential diagnosis for taeniasis and cysticercosis.