Objective: We found the hypomethylation status of CYP11B2 gene in the aldosterone-producing adenomas compared with normal adrenal glands or non-functioning adrenal adenomas and reported that the methylation of promoter region of this gene influenced the mRNA expression in the adrenal cells. Angiotensin II or potassium influenced the methylation status of CYP11B2 gene. In order to clarify the effect of salt intake on the methylation status of CYP11B2 gene, rats were fed with high or low salt diet and the methylation status of CYP11B2 gene in the adrenal gland was examined. Design and Method: Five Wister rats were fed with high, normal and low salt diet for 8 weeks. Plasma and urinary aldosterone, PRA were measured by RIA. The gene expression of CYP11B2 was measured by real time quantitative PCR in the adrenal glands. Isolated DNAs from rat adrenal glands were treated with bisulfite and amplified using primers specific for the human CYP11B2 promoter regions. Results: Plasma and urinary aldosterone and PRA were significantly decreased by high salt diet compared with normal or low salt diet (p < 0.05). High salt diet significantly decreased mRNA levels of CYP11B2 gene and increased metylation ratio of this gene (p < 0.05). Conclusions: High salt diet may influence the methylation ratio of CYP11B2 gene and regulate aldosterone biosynthesis.