Background: Nowadays endoscopies become routine clinical procedures which produce intense anxiety, stress and dissatisfaction for children. Purpose: to evaluate the effect of psychological preparation on coping strategies of children undergoing endoscopy. Research design: A quasi experimental design. It was conducted at endoscopy unit of National Liver Institute Menoufia University. Sample: A convenient sample of 22 children who had liver diseases and undergoing endoscopy. Instruments: five data collection instruments were used; characteristics structured questionnaire, Physiological evaluation sheet, Children's Coping Strategies Checklist (CCSC), Spielberg State-Trait Anxiety Inventory (SSTAI) and Model for End Stage Liver Disease (MELD) Score.Results: there was highly statistical significant difference in coping between study and control group on posttests (p.001). As well, there was highly statistical significant difference in anxiety level between study and control group on posttest (p.01). Conclusion: children in the study group who are engaged in psychological preparation exhibited more effective coping strategies, lower anxiety level on posttests than patients in the control group. Recommendations:The study recommended that psychological preparation should be importantly integrated in endoscopic units as a routine care to enhance children ' coping strategies and lower the negative consequences of this stressful experience.