Colorectal cancer (CRC) is the second leading cause of cancer-related death in the United States. Iraq represent the sixth country incidence rates of colorectal cancer in Asia while India the first country followed by, Yemen, Bangladesh, Egypt and Pakistan. The purpose of presence study is the evaluation of the arginase activity of Iraqi Patient with colorectal disease and other intestinal disease in comparison with other colorectal cancer tests such as CEA, CA 19-9 in Iraqi patients and if it can be helpful in the diagnosis of patients with colorectal cancer and other intestinal disease. The activity of arginase was determined in blood serum was collected from 57 patients included 2 group of patients with colorectal cancer and other intestinal disease, in addition to The control group consisted of 20 healthy blood donors and compared with the level of CEA and CA 19-9. There is significant increase in arginase concentration in all groups versus the control group (P<0.05). CEA levels showed a significant increase only in colorectal cancer and inflammation versus the control group but there is no increase in the levels of in CEA in ulcerative and polyp groups versus the control group (P<0.05). We found the higher range for arginase, CEA and CA19-9 was in left colon rather than right colon and rectum.