Objective：To analyze the polymorphism in human cDNA sequence of prothymosin-α (ProTα) by sequencing analysis. Methods: The cDNA of human ProTα was amplified from cells of peripheral blood and cord blood by RT-PCR．The product of RT-PCR was purified and linked with vector pMD18-T. After cloning and sequencing, the sequence of ProTα cDNA was compared with the standard sequence to analyze the polymorphism in the ProTα cDNA sequence. Results: The cloned ProTα cDNA sequence was different from that of the standard. We found 2 kinds of variations: (1) The nucleotide in 107 position was varied and the nucleotides in 110-121 and 191-205 positions were deleted; (2) The nucleotide in 306 position was deleted, mainly in the 60-80 years old group. Conclusion: We have identified 2 kinds of variations in human ProTα cDNA, but the first 28 amino acid in the N-terminal of cDNA of human ProTα are not involved therefore the variations do not affect the function of human ProTα.