Objective:To investigate the role of TCP1-β in the proliferation of androgen-independent prostate cancer (AIPC). Methods:Androgen-dependent prostate cancer (ADPC) cell line LnCap and AIPC cell line PC3 were chosen as a model. Phenol-red free medium and FBS that was depleted of steroids by charcoal/dextran-treatment were used for the cell culture,to detect the androgen dependence of the cells. RNAi was used to inhibit the TCP1-β expression of PC3-Ad and LnCap cells. Q-PCR and Western blot were used to detect the expression of TCP1-β. The viability or apoptosis of PC3-Ad and LnCap cells was determined by MTT or flow cytometry(FCM) method. STRING was used to analyze the interaction between TCP1-β and AR. Results:The proliferation of LnCap but not PC3 cells was inhibited by androgen deletion. The expression of TCP1-β was significantly decreased when PC3-Ad and LnCap cells were transfected with siRNA of TCP1-β (P < 0.05). The proliferation of PC3-Ad but not LnCap cells was significantly inhibited when TCP1-β expression was inhibited (P = 0.002,P = 0.006). No significant apoptosis was detected in both PC3-Ad and LnCap cells when TCP1-β expression was inhibitied (P = 0.015). Conclusion:Over-expression of TCP1-β may involved into the regulation of AIPC proliferation.