The invention belongs to the technical field of plantation carbon sequestration and particularly relates to a waxberry plantation carbon sequestration improving method. The method comprises the following steps: A, a woodland is selected: a waxberry plantation with the slope less than 25 DEG, the density 525 to 675 trees/hectare and the plantation age 3 to 25 years is selected; B, straw covering iscarried out: straw is used to cover the selected waxberry plantation coverage range in early November of the first year; C, the straw is removed; and D, interplanting of phaseolus spp. in the waxberry plantation is carried out. The straw is used to cover the waxberry plantation, interplanting of phaseolus spp. is carried out after the straw is removed, the biomass carbon in the herb layer and thesoil organic carbon storage in the waxberry plantation are improved through dual effects, the quality of waxberry fruits is also obviously improved, the carbon sequestration ability of the vegetationlayer below the waxberry plantation is obviously improved, and the loss of soil organic carbon can be effectively prevented.