In MDS patients with U2AF1 mutation, due to the cases of MDS-RS (0 case), MDS (5q -) (2 cases) and MDS-U (1 case) were so few, so only 48 cases of MDS-SLD/MLD/EB1/EB2 with U2AF1 mutation were included to analyze the mutation site, mutation load and co mutation gene of U2AF1. This evidence concerns the gene U2AF1 and myelodysplastic syndrome.