Objective:To explore the association between serum 25-hydroxyvitamin D [25-(OH)D] and high-sensitivity C reactive protein (hs-CRP) levels in health check-ups population.Methods:A total of 746 patients who underwent health check-ups at an enterprise unit in Hefei city were selected as the study subjects with an average age of (47.2±15.6) years and 489 males, accounting for 65.5%. Demographical and disease information was collected through questionnaires. Serum 25-(OH)D and hs-CRP levels were measured. The subjects were divided into three groups according to the 25-(OH)D level: non-deficient group (≥50 nmol/L), deficient group (25 nmol/L to 49.9 nmol/L), severely deficient group (<25 nmol/L). C-reactive protein was divided into normal group and high value group by 75% percentile. Multivariate logistic regression was used to analyze the relationship between 25-(OH)D and hs-CRP levels.Results:The proportions of high CRP levels in the severely deficient, deficient, and non-deficient groups were 29.8%, 26.4%, and 17.0%, respectively, and the difference was statistically significant (χ2=6.471， P<0.05). Logistic regression analysis showed that, compared with the non-deficient group of 25-(OH)D, the odds ratios values (95% CI) of the high values of hs-CRP in the deficient group and the severely deficient group of 25-(OH)D were 1.851(1.122 to 3.053) and 2.369(1.227 to 4.573), respectively. Conclusions:Serum 25-(OH)D level is a risk factor for hs-CRP in adults. Nutritional intervention in vitamin D deficient population may be beneficial to reduce the level of inflammation.