It has been proved that adjuvant chemotherapy can improve overall survival, reduce the relapse rate and mortality in colon cancer. Screening out suitable patients to receive adjuvant chemotherapy is the key point. At present, the treatment strategy is almost based on the clinical stage and pathologic high risk factors and it cannot meet the requirements of precision therapy. Combined application of biomarker is helpful in screening patients and improving treatment efficacy. Recently multiple retrospective studies have shown that patients with microsatellite high instability or MMR-deficient CRCs have a more favorable prognosis, at the same time, do not benefit from treatment with adjuvant 5-fluorouracil chemotherapy. The microsatellite status maybe an important reference index and should be used to inform clinical decision-making for adjuvant chemotherapy. Through reviewing the literature, the impact of the microsatellite status on prognosis, predictive significance and decision-making of adjuvant chemotherapy in colon cancer has been expatiated in the paper.