Colorectal cancer (CRC) is now the third most common cause of cancer-related deaths in the world. According to the Iranian Annual National Cancer Registration Report, CRC is the third most common cancer in Iranian women and fifth in men. The incidence of CRC has increased during the last 25 years. CRC screening is an efficient way to reduce the burden of CRC through detection of precursor lesions of cancer or early stage cancer. Iran may benefit even more from screening programs. According to recent studies, the prevalence of colorectal adenoma in first degree relatives of patients diagnosed with CRC is significantly higher than in the average risk population. So, appropriate screening strategies, especially in relatives of patients, should be considered as the first step of CRC screening in Iran.