Background and Study Aim: Ulcerative colitis (UC) is a chronic, idiopathic inflammatory bowel disease characterized by remission of disease activity. Searching for laboratory markers which are simple, sensitive, specific and noninvasive is fundamental to assess the extent of inflammation, activity of the disease, evolution and prognosis which can be used to assess response to treatment and the possibility of relapse. Our aim of the work was to investigate the diagnostic role of fecal calprotectin and serum MMP-9 in determining the activity of ulcerative colitis. Patients and Methods: 71 patients were included in the study and fecal calprotectin, serum MMP-9, ESR and CRP were measured in these patients to determine the disease activity of ulcerative colitis. Results: Fecal calprotectin concentration in the patients with active UC was significantly higher than that in inactive disease and in controls (387.21 ± 44.07 μg/g vs 103.62 ± 119.67 μg/g, 12.44 ± 3.65 μg/g, p = 0.000). Serum MMP-9 was found to be higher in patients with active UC than in patients with inactive disease (11.02 ± 5.29 vs 4.01 ± 1.72 ng/ml, p = 0.000). A significant difference was also found in the patients with active UC of mild, moderate and severe degrees. Also, strong positive correlation was found between fecal calprotectin and serum MMP-9 and the severity of the disease. The area under the curve of the receiver operating characteristics (AUCROC) was 0.949 and 0.941 for fecal calprotectin and serum MMP-9 respectively. Conclusion: Fecal calprotectin and serum MMP-9 can be used to differentiate between active and inactive forms of UC.