Objective Incidence of acute adverse reactions (ADR) of 4 kinds of iodine contrast agents were retrospective analyzed in 10532 cases of CT enhanced scan and 6130 cases of arteriography in our hospital, and to investigate the safety of these 4 types agents in clinical application.Materials and Methods The occurrence of ADR to Iohexol, Ioversol, Iopromide and Iodixanol (expressed as I1, I2, I3 and I4) were recorded in detail from August,2007. 36 months' data were analyzed by Fisher's `Exact Test. The incidences of ADR were calculated, and medicine information and features of adverse reactions induced by these 4 types agents are analyzed. Results: CT enhanced scan and arteriography was performed in 16662 cases, including body enhanced scan, CTA ，CTU and arteriography. Acute adverse reactions occurred in 25 cases, and the incidence of ADR was 0.15%. Among them, 18 cases had mild ADR (0.10%), 7 cases had moderate ADR (0.04%) and 0 cases had severe acute adverse reaction. There was a difference in the incidence of acute adverse reaction between the 4 contrast agents used (X2=5.854, p=0.022). I4 had the highest incidence of ADR, it was 0.32%, and the lowest incidence of ADR occurred in I2, it`s 0.08%. The incidence of ADR with I1 and I3 was 0.14% and 0.18%, respectively. The incidence of ADR in intravenous administration was significantly higher than that in arterial administration（X2=4.655，p=0.036）. Conclusion In this study, the incidence of acute adverse reaction to Iodixanol was the highest, and Ioversol was the lowest. The incidence of ADR in arteriography was significantly lower than that in patients with intravenous administration enhanced CT.