Background: Acceptance of the implantable cardioverter-defibrillator (ICD) device may be affected by a variety of factors. This study aimed to investigate the predictor roles of spiritual well- being, healthcare professionals’ support and shock anxiety in accepting ICD. Methods: This cross-sectional study was conducted on 100 patients with ICD. The data were collected by the Florida Patient Acceptance Scale, Florida Shock Anxiety Scale, Spiritual Well-Being Scale and Healthcare Professionals’ Support Questionnaire. Results: The mean (SD) scores of patient acceptance, shock anxiety, spiritual well-being and healthcare professionals’ support were 65.4 (13.56), 21.93 (8.95), 88.92 (11.78) and 76.41 (10.54), respectively. The results revealed higher acceptance among the participants with lower shock anxiety levels (r = −0.51, P < 0.001), higher mean scores of spiritual well-being (r = 0.33, P = 0.001) and higher healthcare professionals’ support (r = 0.40, P < 0.01). Additionally, the results of linear regression indicated that spiritual well-being, healthcare professionals’ support and shock anxiety predicted 36% of the patient acceptance variance (R = 0.61, R2 = 0.38, adj R2 = 0.36) and shock anxiety and healthcare professionals’ support were the predictors of patient acceptance. Conclusion: The study results indicated that the patients’ mean score of acceptance was relatively high. In addition, the mean scores of shock anxiety, spiritual well-being and healthcare professionals’ support were low, moderate and relatively high, respectively. Conducting healthcare professionals’ support interventions, spiritual therapy and reducing shock anxiety can help patients accept ICDs.