Objective: D-dimer is correlated to the poor prognosis of non-small-cell lung cancer. The study aimed to investigate the association between plasma D-dimer and concomitant mutations in non-small-cell lung cancer. Methods: A total of 517 non-small-cell lung cancer patients were recruited and tested for ALK, BRAF, EGFR, HER2/ERBB2, KRAS, MET, PIK3CA, RET and ROS1 mutationby next-generation sequencing. Multiple gene mutation information, clinical baseline data and laboratory test data were analyzed statistically. Results: All patients were divided into three groups: wild-type group, single-gene mutation group and concomitant mutation group. The analysis of D-dimer, uric acid, gender, family history, smoking history, histology and distant metastasis all showed significant differences in the three groups (p<0.05). D-dimer was considered as a risk factor for concomitant mutations according to the unordered multiple logistic regression analysis. The receiver operating characteristic curve analysis indicated that D-dimer had an important predictive value for the occurrence of concomitant mutations (area under the curve [AUC]: 0.94; sensitivity: 88.71%; specificity: 86.46). There was significantly shorter median progression-free survival in the concomitant mutation group compared with the single mutation group (7.70 months vs 14.00 months; p=0.0133). Conclusion: Plasma D-dimer is significantly associated with concomitant mutations and may be regarded as a potent predictor of concomitant mutations for non-small-cell lung cancer patients.