Objective To explore the clinical characteristics for patients with hemorrhagic transformation(HT) after acute cere‐bral infarction .Methods In this study ,retrospective analysis was performed for 48 patients HT ,which were classified as HI(n=45 ,93 .8% ) ,HI‐1(n=27) ,HI‐2(n=18);PH(n=3 ,6 .3% ) ,PH‐1(n=2) ,PH‐2(n=1) .PH‐2 admission NIHSS score was signifi‐cantly higher than other types of HT .CT scans and MRT were carried out ,infarction area were defined so that we could choose dif‐ferent treatments .Results The total cases with hemorrhage time within 1 -2 weeks after infarction was 28(58 .3% ) ,while 14 (29 .2% )occured within 1 week .The relationship between HT location and infarction area:25 cases(52 .1% ) occurred cerebral lobe infarction ,for which hemorrhage lesion was located in cortex and(or) subcortical;11 cases (22 .9% ) occurred deep brain parenchy‐ma infarction ,for which hemorrhagic lesion was located inside or on the edge of infarcts;8 cases were lobes and deep infarction ,3 cases were cerebellar infarction ,1 case was brain stem infarction ,all of the hemorrhagic lesion was inside the infarcts .The relation‐ship between HT and infarct size:31 cases(64 .6% ) occured secondary to large area acute cerebral infarction ,14 cases(29 .2% ) oc‐cured secondary to small area of cerebral infarction ,3 cases(6 .3% ) occured secondary to lacunar infarction .Hemorrhage of the HI patients was in the cortex and the subcortical white matter ,with shapes of deep brain dot ,patchy ,funicular or gyrus .Hematoma was formed in cerebral infarction for PH patients ,which mainly located in basal ganglia .Conclusion The HT occurrence is closely relat‐ed to the infarction area and size .Patients with Large area and cerebral lobe infarction have high opportunity for complication of HT .HT usually occurs within 1-2 weeks after cerebral infarction ,during which brain CT or MRI should be routinely reexamined .