Fecal calprotectin (FC) is a marker used for the differential diagnosis of inflammatory bowel disease (IBD). FC is also used to determine the effects of treatment and recurrence prediction because of its non-decomposition by bacteria, relative week stability at room temperature, and its uniform distribution within feces. Healthy male and female adults between the age of 30 and 80 living in Jeju were selected for this study. The FC concentration in the healthy control group (N=45) was distributed widely as 0∼545.9 μg/g and showed a significant difference with age in healthy adults. The FC concentration in adults over 70 years old (80.6 years on average) was 160.3 μg/g. The result is approximately 10 times higher than in adults below 50 years (44 years on average), with FC concentrations at 15.88 μg/g. Moreover, adults over 50 years, with an average age of 59.6, had FC concentrations of 35.46 μg/g, which were two times higher than the below 50-year-old group, confirming the significant correlation between age and FC concentration. As the FC test is a non-invasive and cost-effective objective marker in IBD tests, a suitable cutoff value is required for different ages. This study provides the baseline data for differential diagnoses.