ABSTRACT Background: Colorectal Cancer (CRC) is considered the third most deadly and fourth most commonly diagnosed cancer in the world. Objective: The aim of the present study was to compare serum levels of growth differentiation factor-15 (GDF-15) in patients with CRC and in those healthy control subjects. Patients and methods: The study included 60 subjects that were divided in two groups: Group Ι included 30 patients diagnosed with colorectal cancer and group ΙΙ that included 30 healthy volunteers as control group. They didn`t have any acute or chronic diseases. All subjects of this study were subjected to full history taking, clinical examination and laboratory investigations. The study was conducted at Internal Medicine Department (gastroenterology and endoscopy unit), Faculty of Medicine, Zagazig University. Results: The study comprised 35 males (58.3%) and 25 females (41.7%), with a mean age of 61 ± 9 years. Twenty-six participants were from urban areas (43.3%) and 34 from rural areas (56.7%). Thirteen participants had a suspicious occupational exposure (21.7%) and 27 were smokers (45%). Mean BMI of all participants was 31 ± 6 kg/m2 with no statistically significant differences between the studied groups. Regarding Hb level and GDF-15, there were statistically significant differences between CRC group and control group where Hb was higher in the control group, while GDF 15 was higher in CRC group. Conclusion: Growth differentiation factor 15 (GDF-15) could be used as a valuable independent biomarker for screening CRC. Keywords: Colorectal Cancer, GDF-15, CRP, CT scan.