Abstract： Objective To explore the effect of allisartan isoproxil in treating elderly patients with mild-to-moderate hypertension and its influence on the blood pressure control compliance rate and target organ protec-tion.Methods One hundred and twenty elderly patients with mild-to-moderate hypertension admitted to Chengdu Fifth People's Hospital from January 2021 to March 2022 were studied and divided into control group(n=60,odd number,losartan potassium treatment)and experimental group(n=60,even number,al-lisartan isoproxil treatment)according to the odd-even number method,and both groups were treated for 12 months.The therapeutic effect and blood pressure changes were compared between the two groups,and the blood pressure variability and target organ indicators in the two groups were observed before and after treat-ment,and the adverse reactions were recorded in both groups.Results The total effective rates of treatment in experimental group and control group were 95.00％and 83.33％respectively(P＜0.05).The average pressure reduction amplitudes,SBP trough-to-peak ratios(T/P)and blood pressure compliance rates of systolic blood pressure(SBP)and diastolic blood pressure(DBP)in experimental group were significantly higher than those in control group(P＜0.05).After treatment,the standard deviation of 24 h mean SBP(24 h SBPSD),stand-ard deviation of 24 h mean DBP(24 h DBPSD),standard deviation of mean daytime SBP(dSBPSD),standard deviation of mean nighttime SBP(nSBPSD),standard deviation of mean daytime DBP(dDBPSD),standard deviation of mean nighttime DBP(nDBPSD)and target organ indicators of carotid intima-media thickness(IMT),left ventricular mass index(LVMI)and 24 h urinary microalbumin(MA)were significantly de-creased in both groups(P＜0.05),and the above indicators in experimental groups were lower than those in control group(P＜0.05),and the endogenous creatinine clearance rate(Ccr)in both groups was significantly increased(P＜0.05),and the indicator was higher in experimental group than that in control group(P＜0.05).The total incidence rates of adverse reactions in control group and experimental group were 8.33％and 5.01％respectively(P＞0.05).Conclusion Allisartan isoproxil has a significant efficacy in the treatment of elderly patients with mild-to-moderate hypertension,and it can effectively improve the blood pressure changes and blood pressure variability,and strengthen the target organ protection,and it is safe and effective and is suitable for clinical promotion and application.