Three kinds of biochar-based nitrogenous fertilizer(BBNF), which were composited with ammonium nitrate by simple-blending process, adsorbent process and reactive process, respectively, were produced. After that properties of the new BBNF were determined and their sustained release characteristics were evaluated. The results show that the pH values of all the three BBNF are all lower than that of the raw biochar. The BBNF prepared by reactive process loads maximum ammonium nitrate, followed by the BBNF prepared by adsorption process; the least is the BBNF prepared by blending process. The retention capacity of BBNF prepared by reactive process is better than the other two. The cumulative release rate of the three BBNF in aqueous solution is in line with the “S”-type release model. Compared with ammonium nitrate, all of the three BBNF have effectively controlled-release effect on nitrogen, and the BBNF produced by reactive process has the best effect.