The invention discloses nitrogen-doped grading porous carbon microspheres. The nitrogen-doped grading porous carbon microspheres are prepared by performing hydrothermal reaction on glucose and a nitrogen-containing compound and then performing activation, wherein the specific surface area is high and is 1160 to 1791 m<2> / 1, the pore diameter is distributed uniformly and the micropore content is high. The preparation method comprises the following steps: 1) preparing a nitrogen-containing precursor, adding the glucose and the nitrogen-containing compound into water, stirring uniformly, reacting, filtering, washing and drying to obtain the nitrogen-containing precursor; 2) carbonizing and activating the nitrogen-containing precursor, mixing the nitrogen-containing precursor and an alkaline inorganic matter, soaking into water, stirring and drying, and calcining and activating to obtain the nitrogen-doped modified grading porous carbon microspheres; and 3) performing aftertreatment on thenitrogen-doped modified grading porous carbon microspheres, soaking the nitrogen-doped modified grading porous carbon microspheres in a hydrochloric acid solution, washing, filtering, drying and grinding. When the nitrogen-doped grading porous carbon microspheres serve as supercapacitor electrode materials, the specific electric capacity is 248 to 407 F / g. The nitrogen-doped grading porous carbonmicrospheres have an application prospect in the fields of supercapacitors, lithium ion batteries and electric catalysis.