Objective:To observe therapeutic effect of aerobic exercise on blood pressure and vasoactive mediators in patients with isolated diastolic hypertension (IDH).Methods:A total of 93 recently diagnosed IDH patients were se- lected and randomly divided into exercise intervention group (n=47,received aerobic exercise,twice/d,50~80 min/time for six months)and control group (n=46,didn't receive aerobic exercise).Office blood pressure (OBP), ambulatory blood pressure monitoring (ABPM)and levels of vasoactive mediators were measured and compared be- tween two groups before and six months after intervention.Results:There were no significant difference in levels of OBP,ABPM indexes and related vasoactive mediators between two groups before intervention (P>0.05 all).Com- pared with before intervention,after six-month intervention,there were significant reductions in levels of office di-astolic blood pressure (ODBP),mean DBP (mDBP),daytime DBP (dDBP)and nighttime DBP (nDBP)in both groups (P<0.05 or <0.01);compared with control group,there were significant reductions in levels of ODBP [(89.23±14.70)mmHg vs.(79.26±13.18)mmHg],mDBP [(86.51±14.30)mmHg vs.(77.20±12.45)mm- Hg],dDBP [(87.93±12.16)mmHg vs.(78.02±11.27)mmHg]and nDBP [(83.18±12.57)mmHg vs.(74.22 ±11.36)mmHg]in exercise intervention group,P<0.05 all.Compared with control group,after six-month inter- vention,there were significant rise in levels of adrenomedulin (AM)[(36.75±5.13)ng/L vs.(47.59±6.82)ng/L]and prostaglandinI2 (PGI2)[(89.55±16.31)ng/L vs.(99.24±18.20)ng/L],and significant reductions in levels of angiotensin Ⅱ (AngⅡ)[(98.30± 15.65)ng/L vs.(91.28±17.40)ng/L]and thromboxane A2 (TXA2 )[(93.61±15.27)ng/L vs.(80.24±12.31)ng/L]in exercise intervention group,P<0.05 all.Conclusion:Aer- obic exercise can significantly lower blood pressure and correct vasoactive mediator level disorder in IDH patients.