The purpose of this study is to investigate the effect of supportive educational Nurse-led intervention on anxiety and sleep in patients before bypass grafting surgery. It's a randomized control trial investigation. Patients who are scheduled for bypass grafting surgery are subjected to this study. Total numbers of 160 eligible patients were categorized in to two groups: Control & Intervention groups. The Inclusion criteria were: having consent to participate, scheduled elective bypass grafting surgery, ability to speak Persian, having no sleep disorder before hospitalization (self-reported), having no mental disorder (self-reported). The Exclusion criteria were: reluctant to continue, having previous bypass grafting surgery, having both bypass grafting surgery and valve replacement or other surgery at the same time, occur any acute fatal hemodynamic condition or any problem which cancel the surgery. The first day of hospitalization, they should complete informed consent, demographic information; spielberger state anxiety and Groningen sleep quality scale. In control group, spielberger state anxiety is filled the night before the surgery and Groningen sleep quality scale is filled on the morning of the surgery. Intervention group perform supportive educational Nurse-led intervention during hospitalization before surgery. the supportive educational Nurse-led intervention consists of communicate with patient, give general information about surgery, encourage patient to talk about anxiety and its causes, introduce the stress management techniques such as Benson muscle relaxation, deep breathing, praying, guided imagery. Then they learn one of these techniques which the patient choose and practice it during the sessions.