Ulcerative colitis (UC) is a chronic, idiopathic, inflammatory large bowel disease with recurrent variable periods of exacerbation. The aim of the current study is to evaluate the correlation of UCEIS with fecal calprotectin (FC) level to assess disease activity in UC patients in order to determine whether FC can prognosticate clinical outcome and disease activity of UC instead of colonoscopic evaluation. Our endoscopic investigations revealed the extension of UC as the following: proctitis (11.6%), procto-sigmoiditis (18.5%), left-sided colitis (15.8%), extensive colitis (11.7%), and normal endoscopy (42.4%). Conclusively, we suggest that FC can be used as a reliable tool to evaluate disease activity in ulcerative colitis patients. Moreover, our findings indicate a significant correlation between FC level and mucosal healing.