Background: Insomnia is a highly prevalent complaint among elderly; it is associated with significant morbidity and is often a persistent problem, particularly in older adults . Aim of the study: The present study aimed to dete rmine the prevalence and risk factors of insomnia and its effect on quality of life among elderly. Design : a cross-sectional descriptive design was utilized to conduct this study . Sample: a stratified random sample of 107 elderly subjects attending the two geriatric social clubs in Zagazig city. Tools: Fo ur tools were used in the present study; a structured interview questionnaire, Athens insomnia scale, The Geriatric Depression Scale: short form, and The Medical Outcomes Study Short Form Health Survey (SF-36). Results: The prevalence of insomnia among the studied elderly was 33.6%, while difficulty initiating sleep was the most prevalent insomnia symptoms among them. Unmarried status, depressive status, smoking, eating before bedtime, daytime long naps, irregular sleep hours were significantly associated with insomnia. Suffering from asthma, nocturia, apnea, and total number of daily medications were significantly associated with insomnia. Insomniac elderly had significantly lower scores in all quality of life domains, except the social functioning domain. Conclusion : One-third of the studied elderly was suffering insomnia which was associated with many different factors. Insomnia was associated with worse quality of life in older adults. Recommendations: Healt h instructions and educational programs should be conducted for elderly individuals with insomnia to improve their sleeping pattern and quality of life .