Introduction: A fall is a sudden descent on the ground or other lower levels. It is a serious safety threat for hospitalized patients. Coronary artery bypass graft (CABG) surgery as an open heart surgery has complications such as cardiac arrhythmias and delirium that can increase the risk of fall. Objective: This study aims to determine the risk of falls in patients after CABG surgery and investigate its associated factors. Matetials and Methods: This cross-sectional study was conducted on 302 patients undergoing CABG surgery in a specialized hospital in Rasht City, Iran, from November 2019 to July 2020. They were selected by a sequential sampling method. The data collection instrument included demographic information, disease-related factors, surgery-related factors (before, during, after), and the Morse fall scale (MFS) checklist. The study data were collected after the patient's surgery and transfer from the intensive care unit to the surgical ward. Descriptive statistics, as well as the Kolmogorov Smirnov, Wilcoxon, Mann-Whitney U, Kruskal-Wallis, and Spearman correlation, were used to analyze the collected data. A rank regression model was used to determine the factors related to the risk of falls in patients. Results: The mean ±SD age of participants was 59.35 ±8.37 years. About 70.53% of the patients were male, and 46.03% were overweight (Body Mass Index ranged 25-29.9 kg/m2). The majority of patients at the time of admission to the surgical ward and before surgery (92.72%) had no risk of falls. After surgery and transfer to the surgical ward, 82.12% had a low risk of falls. The mean risk of falling was higher in patients over 60 years (P <0.05). With decreasing hemoglobin values on the morning of surgery, the risk of postoperative fall increased (P = 0.046, r = -0.115). The sodium level on the morning of surgery had a significant negative correlation (P = 0.040, r = -0.118) with the risk of falling, but urea level on the morning of surgery had a significant positive correlation (P = 0.001, r = 0.212) with the risk of falling. Using regression model, the results showed that with increasing age (B = 0.23, 95%CI; 0.07-0.39, P = 0.003), history of high blood pressure (B= 3.5, 95%CI: -0.69-0.39, P = 0.003), decrease in hemoglobin (B = -5.47, 95%CI; -10.2- -0.6, P = 0.02), an increase in creatinine (B = 17.73, 95%CI; 8.17-27.29, P = 0.001) and urea (B = 6.09, 95%CI; 2.57-9.61, P = 0.001) before the surgery, the risk of fall after CABG surgery increases. Conclusion: Several factors can increase the risk of falls after CABG surgery. Considering that the risk of falls in patients undergoing CABG surgery in most medical centers is examined only at the beginning of admission, it is recommended to consider the possibility of postoperative falls based on the predicting variables.