Objective To investigate the correlation of single nucleotide polymorphism (SNP) of C-reactive protein(CRP) with hypertension induced by obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods A total of 300 male patients diagnosed as severe OSAHS by polysomnography in our department from January 2006 to December 2012 were enrolled in this study. One hundred and forty-five of them were identified having hypertension. Another 100 healthy males randomly sampled served as normal controls. SNPs of the promoter region of CRP rs3091244 and rs1205 were detected in those OSAHS patients with or without hypertension, and health individuals. Statistical analysis was performed to evaluate the correlation between SNP of CRP and OSAHS with or without hypertension. Results The frequency of CT genotype in CRP rs3091244 was significantly higher in the OSAHS patients with hypertension than those without (17% vs 7%), so was the frequency of T allele in rs3091244 (9% vs 3%). The frequency of CC genotype in CRP rs1205 was also higher in the OSAHS patients with hypertension than those without (25% vs 11%). Conclusion CRP SNP is correlated with hypertension in the OSAHS patients. The CT genotype of CRP rs3091244 and the CC genotype of rs1205 may cause chronic inflammation and promote the occurrence of hypertension through enhancing serum CRP level.