The nitration of tetraacetyldibenzylhexaazaisowutzitane by CAN and NaNO₂ in chloroform in the presence of phase transfer catalysts was kept for 8 hours at 40 ℃. The remained benzyl groups were nitrated successfully and the corresponding products-tetraacetyldinitrohexaazaisowutzitane was obtained with a yield of 66%. The mechanism of the nitration of N-benzyl group by CAN in the presence of phase transfer catalysts is discussed.