Objective To investigate the prognostic value of prognostic nutritional index PNI in the advanced colorectal cancer patients who received the fruquintinib as third-line therapy. Method From November 2017 to June 2020 33 patients with advanced colorectal cancer were selected from Jingzhou Central Hospital and Tongji Hospital Cancer Tongji Medical College Affiliated Huazhong University of Science and Technology. PNI prognostic nutritional index PLR platelet lymphocyte ratio and LMR lymphocyte monocyte ratio were calculated. Cox proportional hazards regression models and Kaplan-Meier curve and Log rank test were used to evaluate the impact on survival. Result According to receiver operating characteristic ROC curves the cut-off value for PNI was 46. 95. The result of univariate analysis showed that PNI HGB NLR and LMR were significantly correlated with overall survival OS . Multivariate analysis showed the PNI was independent prognostic factor of OS. The one-year survival rate and the median overall survival for PNIlow patients were 9. 894% 95%CI = 8. 300-23. 566 and 6. 700 months 95%CI = 5. 524-7. 876 while the one-year survival rate and the mOS for the PNI-high patients were 42. 218% 95%CI = 22. 496-46. 378 P<0. 05 and 11. 400 months 95%CI = 6. 123-16. 677 P<0. 05 . The median progression free survival mPFS for PNI-low and PNI-high patients were 2. 200 months 95%CI = 1. 278- 3. 122 and 3. 067 months 95%CI = 1. 095-5. 039 P>0. 05 . Conclusion PNI could be a useful prognostic indicator for advanced colorectal cancer patients who received the fruquintinib as third line treatment.