Objective To systematically review the value of the perfusion paramenters of Ktrans and Kep of dynamic contrast enhanced MRI(DCE-MRI) in distinguishing different histological grades of rectal cancer. Methods Databases such as PubMed, EMbase, Web of Science, The Cochrane Library (Issue 1, 2017), CBM, CNKI, WanFang Data and VIP were searched from 1990 to Feb 6th, 2017 to collect the studies according to the criteria. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies and then meta-analysis was performed by using STATA 12.0 software. Results A total of 11 studies involving 618 patients were included. The results of meta-analysis showed that there was significant difference of Ktrans between poorly differentiated grade and moderately-well differentiated grade (SMD=1.123, 95% CI 0.334 to 1.911,P=0.005), but there was no significant difference of Kep between these two groups (SMD=0.233, 95% CI –0.173 to 0.639,P=0.260). Conclusion Current evidence shows that Ktrans can be used to distinguish different histological grades of rectal cancer. The clinical application value of Kep still needs large sample original studies to further verify.