Diurnal variation of soil respiration affected by fertilization at various growth stages of maize in black soil was in-vestigated with the static dark chamber method and gas chromatograph technique at the Hailun Agricultural Ecology Station.Results show that during the growth stages of maize,soil respiration rate displayed an obvious seasonal curve,with peaks occurring on the 23th,37th,50th,63th,87th and 110th days after seedling emergence,and the highest on the 87 th day,and a downward trend till the crop was harvested.Respiration rate of the rhizospheric soil followed a curve similar to that of the soil,while respiration rate of bulk soil was mainly affected by air temperature.The corn growing in the soil significantly affected soil respiration rate,which rose when the plant grew and decline when it got snile,showing a similar curve.Fertilization also significantly affected the respiration rates of soil and rhizospheric soil,but little of the bulk soil.Based on the entire growth period of maize,Treatment NPKOM was the highest in soil respiration rate and rhizospheric respiration rate,ranging in C 27.5～474 mg m^-2h^-1;Treatments NPK and NP were quite close,varying in the range of C 25.9～339 mg m^-2h^-1 and 29.5～358 mg m^-2h^-1,respectively;and Treatments NK and CK in the range of C 28.4～208 mg m^-2h^-1 and C 22.1～184 mg m^-2h^-1,respectively.In terms of the effect of fertilization,the treatments followed an order of NPKOM>NPK>NP>CK>NK.Through the whole growth period of maize,cumulative soil respiration peaked at the elongating-booting stage and milkyriping stage,following a doublet curve,whereas the cumulative respiration of bulk soil showed a peak at the elongating-booting stage,following a parabolic curve,and that of rhizospheric soil was the lowest at the seedling stage,peaked at the milkyriping stage,and decline afterwards.