Objective To investigate the effect of interleukin-17 (IL-17) on macrophage polarization in DOC/ salt hypertensive rats. Methods Thirty male right uninephrectomized SD rats were treated with 0.1%KCl and 1%NaCl in the drinking water for 2 weeks and randomly divided to three groups: vehicle control rats (CON group); DOC treated group (DOC group); DOC and IL-17 antibody treated group (DOC+ IL-17 antibody group). Systolic blood pressure (SBP) was measured biweekly using the tail-cuff method. The extent of myocardial interstitial fibrosis was analyzed by sirius red staining. CD11c and CD206 were analyzed by immunohistochemistry. Expressions of mRNA of inducible nitric oxide synthases (iNOS) and arginase 1 (Arg1) were determined by real time PCR.Western blotting assay was performed to detect the protein expression of IL-17, iNOS and Arg1. Results There was significant difference in systolic blood pressure among three groups (P < 0.05). The ratio of collagen area to total area of visual field in doc group was higher than that in control group (P < 0.05); after neutralization with IL-17 antibody, the ratio of collagen area to total visual field area in the doc + IL-17 antibody group was lower than that in the doc group (P < 0.05). The expression of iNOS and Arg1 mRNA and the expression of IL-17, iNOS, Arg1, CD11c and CD206 protein were increased in DOC group compared with CON group (P > 0.05). After neutralizing with IL-17 antibody, the expression of iNOS and Arg1 mRNA in DOC+IL-17 antibody group was significantly lower than that of the DOC group (P < 0.05), and the expression of IL-17, iNOS, Arg1, CD11c and CD206 protein was decreased (P < 0.05). Conclusions Macrophage polarization is likely to be associated with IL-17 in DOC/salt hypertensive rats.