The preparation of N, N-dibutyl-m-aminophenol from m-aminophenol and n-chlorobutane using water as solvent was optimized. The results showed that the optimized conditions for the synthesis of N,N-dibutyl-m-aminophenol were the following: n(m-aminophenol): n(n-chlorobutane): n(CuI)=1: 2: 0.06, reaction time of 6.5 h, reaction temperature of about 105~110 ℃ and reaction pressure of about 0.2~0.5 MPa. Under these conditions, the yield of the N, N-dibutyl-m-aminophenol was up to 96.7% and the purity that was determined by liquid chromatography was above 99%. By the fine control of the reaction pressure and the pH of reaction solution, the selectivity of 98.5% was achieved. In this work, the formation of the two side-products including 3-(butylamino)phenol and 3-butoxy-N,N-dibutylaniline was effectively inhibited via the control of the reaction pressure and the pH value of re-action solution. This optimized synthesis process provides a new idea for the fabrication of N,N-di-n-butyl m-aminophenol.