Objectives We investigated differences in high-sensitivity C-reactive protein (hs-CRP) levels by age group according to working hours, socioeconomic level, health behavior and status, and occupational class, and aimed to identify factors affecting hs-CRP levels in various age groups using data from the Korean National Health and Nutrition Examination from 2016 to 2018. Methods: The study included a total of 4,786 male wage workers across the nation, aged between 19 and 65. Data from 4,674 workers were analyzed using multiple logistic regression analysis. Results: Obesity, metabolic syndrome, and weekly working hours were associated with hs-CRP, a biomarker of inflammation. Participants with a body mass index (BMI) ≥25.0 kg/m2 showed significantly higher hs-CRP levels than those with a BMI 23.0 to 25.0 kg/m2. Workers with high-risk drinking and metabolic syndrome showed significantly higher hs-CRP levels in the 50 to 65 years group. Obesity, walking 0 to 149 min/wk, and working ≥61 hours a week were associated with significantly higher hs-CRP levels in the 35 to 49 years group. The factors that significantly affected hs-CRP levels were different among age groups. Conclusion: Plans to adjust working hours should be considered health behaviors, such as drinking and physical activity, and health conditions, such as metabolic syndrome and obesity, according to workers’ age.