PCR direct sequencing is a method which combined PCR amplification with nucleic acid sequencing technique. According to this technique, direct sequencing DNA strand of PCR amplification using PCR primer, α-³⁵ S dATP and Taq DNA polymerase. The experiment showed that it is simple, rapid and stable. This method was used to analvze the tumor suppressor gene p53 mutation in human esophageal eancer. It was found that there were point mutation,insertion and deletion frameshift mutation of p53 gene in human esophageal cancer. Intron 5 and 8 sequences of p53 gene in human and Rhesus monkey were sequenced and in monkey they are 81 and 92 nucleotides respectively.