A comparative observation about histological and histochemical study were made onthe preservating methods of local ischemic kidney of dogs.The methods of this exp-eriment were divided into five groups:A.Local hypothermia;B.Hypothermic perfu-sion solution 500ml,4℃,containing Procaine 450 mg and Heparin 100 mg,infusedinto renal artery;C.Hypothermic perfusion solution 500ml,4℃,containing 20% Ma-nniton 32ml,25% MgSO_4 0.36 ml,Heparin 100 ml,infused into renal artery;D.Localhypothermia and heparin 30 mg injected into the same vessel.E.Local room tem-perature.The specimens were taken from the kidneys of the experimental dogs atvarious period after treated with every method.The results were as follows;A,D and E group presented irreversible histological changes within 4 hoursaftertreatment.Four hours later,the reaction of SDH,ATPase,AlPase werenegative.It suggested that the kidney damage was serious,as well as expressed thatthe effect of these preservating methods for ischemic kidney are not satisfactory.In B group,the histological and histochemical alteration is very light and almostreversible,during 60 days after treatment.In C group,hypothermic perfusionsolution containing Mannitol,MgSO_4 etc either during experiment or follow observa-tion for 60 days,no histological and histochemical alterations were found.It indica-ted that this method is an ideal perservating technique for ischemic kidney.