Disclosed is a method for micro-column enrichment sample injection, using a micro-extraction column having an extraction function as a sample injection needle, allowing a sample to flow through the sample injection needle, during which an analyte is extracted into an extraction medium inside the sample injection needle; then, keeping the sample injection needle filled with an organic solvent for a certain period of time, so that the extracted analyte is dissolved in the organic solvent inside the micro-extraction column to form a sample injection solution; finally, sealing one end of the sample injection needle and inserting the other end directly into a gas chromatograph injection inlet, such that the sample injection solution is automatically released from the sample injection needle into the injection inlet by thermal expansion to complete the sample injection operation. The method integrates separation, enrichment and sample injection, and the sample and the organic solvent used are in small amounts, and
