Background: Colorectal cancer (CRC) is one of the most common cancers worldwide and it is one of the most commonly diagnosed types of cancer at an older age. The gerontological nurse is one of the professionals who act as an educator, health promoter, direct care provider in screening and motivator for older adults to adopt a healthy lifestyle behavior for early detection and prevention of CRC.Aim: The present study aimed to determine the effect of nursing interventions on knowledge and perceptions regarding colorectal cancer among community-dwelling older adults. Research design: Quasi experimental design was used in this study.Setting:The study was conducted in El-Waffa club of elderly persons at Alexandria, Egypt. Sampling:Sixty older adults aged 60 years and above were recruited in the study, who have no cognitive impairment, have no or mild depression, able to read and write and not currently diagnosed with colorectal cancer. Method:Six tools were used as follows: Mini-Mental State Examination Scale, Geriatric Depression Scale Short Form, Older Adults Socio-Demographic and Clinical Data Structured Interview Schedule, Colorectal Cancer Knowledge Questionnaire, Colorectal Cancer Perceptions scale, and older adults' health practices regarding prevention of colorectal cancer. Results: Current study revealed that mean post-test practices and perceptions scores are significantly higher than pre-test scores regarding colorectal cancer among the study subjects. Conclusion:  Nursing interventions were significantly improved the studied seniors' practices, perceptions regarding CRC. Recommendations: Raising awareness of the public about CRC, its management, its prevention, and CRC screening measures in all various health settings.