The gene PC-1 was identified as a novel gene that expressed higher in the much more malignant human prostate cancer cell lines and its translation product meets some points of transcription factors. In order to study the transcriptional activation activity of PC-1，firstly, the yeast two-hybrid system was used and the whole length as well as various regions of PC-1cDNA were cloned into the expression vector pAS2-1 and transfected into the yeast cell line CG-1945 respectively, the result of the reporter genes lacZ and His3 activation assay showed that PC-1 had transcriptional activation activity and this activity was mapped within its N terminal 46 amino acids. Then，the various regions of PC-1 cDNA were cloned into the expression vector pZHO1 and cotransfected with the pTRE-luc plasmid of the reporter gene into COS7 and C4-2 mammalian cells, the 46 amino acids in the N terminal of PC-1 were found to have transcriptional activation activity by the firefly relative luciferase activity assay.