Background: According to Globocan statistics in 2018, there were estimated 1.8 million cases of colorectal cancer and 881,000 deaths. The rate of colorectal cancer is tending to increase in people under 50 years old. According to the 2017 American Society for Gastrointestinal Endoscopy guidelines, Colonoscopy every 5 years beginning 10 years before the age at diagnosis of the youngest affect interval or age 40, whichever is earlier; for those with a single first-degree relative with colorectal cancer in whom no significant neoplasia appears by age 60 years, physicians can offer expanding the interval between colonoscopies. Objectives: (1) T o describe clinical features, endoscopic images, histopathology of polyps and colorectal cancer of first-degree relatives with colorectal cancer. (2) To determine the relationship between risk polyps and colorectal cancer with some factors. Materials and method: Cross-sectional study analyzing all first-degree relatives aged ≥ 40 years or approximately 10 years younger than the age of the patient diagnosed with colorectal cancer undergoing colonoscopy at the Functional Examination Department, Gia Dinh People’s Hospital during the period from June 2019 to December 2019. Results: In 85 cases: The main features of endoscopy were: rectal polyps 47.3%, sizes < 5 mm 63.9%, multiple polyps 52.7%, sessile 91.7% and smooth surface 88.9%. Regarding histopathological characteristics: the proportion of adenomatous polyps and serrated polyps is nearly equal. Mild dysplasia accounts for the highest rate of 84.2%, high dysplasia accounting for 15.8%. There was 1 case of colorectal cancer, in the sigmoid colon, an ulcerative cancer. Factor related to colorectal polyps and colorectal cancer is age, other factors (gender, smoking, alcohol and abesity) didn’t relate. Conclusion: Our result shows that the majority of polyps are located in the rectum, adenomatous polyps and serrated polyps account for nearly equal proportions, there is a relationship between colon polyps and age, there is no relationship between colon polyps. with gender, smoking, alcohol and obesity. Key words: Colonoscopy, colorectal cancer, first-degree relative, polyp.