Most gastrointestinal lesions cause iron-deficiency anemia. Endoscopy of the upper and lower digestive tracts is indicated for IDA patients because most sources of gastrointestinal hemorrhage can be found. Clinical history can predict positive GI endoscopic findings, but its sensitivity in detecting specific lesions, including GI neoplasia, is limited. This study included 1064 IDA patients who had upper and lower GI endoscopies to determine the efficacy of upper and lower endoscopy in diagnosing gastrointestinal causes of iron deficiency anemia in Egyptian individuals. According to our findings, the most common cause of Fe deficiency anemia in upper gastrointestinal lesions (39.8 %) was peptic ulcer, whether gastric or duodenal, followed by angiodysplasia (11.85 %). Colorectal cancer (31.4 percent) was the most common cause of Fe deficiency anemia in lower gastrointestinal lesions discovered by colonoscopy, followed by lower gastrointestinal angiodysplasia (2.7 %). There was a high prevalence of neoplasm in IDA patients. 303 of 700 patients with iron deficiency anemia developed gastrointestinal neoplasm, with 82 instances pathologically proving to be upper gastrointestinal adenocarcinoma and 221 cases being colorectal cancer. In 18 IDA patients, combined lesions were seen. Upper and lower GI endoscopies are beneficial in diagnosing Iron deficiency anemia, says this study. In elderly patients with iron deficiency anemia, gastrointestinal cancers are prevalent. Peptic ulcers are the most prevalent upper GI lesion in Egyptians.