The invention discloses a chemical weeding method for a young fir forest. The chemical weeding method is characterized by comprising the following steps that S1, the types of weeds in the forest are counted; S2, herbicides are selected, wherein the types of the herbicides are selected according to the types of the weeds in the forest; S3, the herbicides are used according to different modes, wherein the different modes include time difference, height difference and resistance difference; S4, herbicide spraying modes include a conventional spraying method and a manual sprinkling method; S5, herbicide use moments are determined according to growth rhythm and climate conditions; S6, remediation measures include drip washing, quick-acting fertilizer application, pesticide alleviator spraying and affected organ removal; S7, spraying seasons and frequency are selected.