The invention relates to the field of fertilization equipment for agriculture and forestry, in particular to a quantitative fertilization apparatus for agriculture and forestry, comprising a frame, atraction rack, traveling wheels, and a quantitative ditching fertilizing device; the traction rack is fitted to the front end of the frame; the traveling wheels are fitted to the frame; the quantitative ditching fertilizing device is fitted to the middle of the frame and comprises a ditching plow, a guide pipe and a quantitative scattering device; the quantitative scattering device is fitted to the frame; one end of the guide pipe is communicated with the quantitative scattering device, and the other end of the guide pipe is communicated with the ditching plow. When the ditching plow of the quantitative fertilization apparatus for agriculture and forestry performs ditching, the quantitative scattering device guides a fertilizer from the guide pipe into holes made with the ditching plow; therefore, quantitative precise scattering of the fertilizer is achieved.