Abstract: In order to verify the calculation code and nuclear data used in the theoretical calculation of the accelerator driven sub-critical system (ADS) sub-critical reactor design, a stainless steel component was used as a neutron absorber in the lead-cooled core of the ADS Venus-Ⅱ zero-power facility, and reactivity value of stainless steel neutron absorber was measured with the periodic method. The experimental results show that the reactivity value of stainless steel neutron absorber decreases with the increase of the distance between the rod and the center. The experimental value is close to the theoretical value, and they have similar variation trend. Experimentally validated theoretical calculation code and nuclear data can be used in ADS sub-critical reactor design.