to observe the protective effect of antihypertensive kidney-replenishing formula granule on early kidney damage by detecting content of renal collagen protein and observing structure of endodermis of arteria renalis with electron microscope.Methods:the spontaneous hypertensive rats were randomly divided to high dosage granule group, low dosage granule group, Nitrendipine group, and sodium chloride group. Blood pressure were detected prior to and after treatment. After 8 weeks of treatment, urine at 24 hour point was collected. Malb、β2-MG were detected with radio-immunity method，the rats were sacrificed to analyze kidney and arteria renalis by image analyzer and electron microscope.Results:there was no significant difference between antihypertensive effect of the granule groups and that of the Nitrendipine group (P>0.05); the treatment groups had better excretion of Malb、β2-MG than the control group (P<0.05); The treatment group could significantly bring down the content of renal collagen protein by which kidney parenchyma damage could be reversed (P<0.05).Conclusion:antihypertensive kidney-replenishing formula granule has definite antihypertensive and kidney protection effect, as shown by promotion of excretion of Malb、β2-MG, and reversion of damage to renal parenchyma and arteria renalis.