Introduction: Hospital length of stay (LOS) is one of the measurable indicators which can be used to evaluate hospital administration, operative performance, and quality of patient care. Prolonged LOS has been associated with poor outcomes in patients and inefficient use of hospital resources. Due to the scarcity of findings in this field in Malaysia, this study aims to identify the factors affecting LOS. Methods: A single health facility-based retrospective cross-sectional study was conducted in Hospital Serdang. Data of patients admitted to the surgical ward from 2017 to 2021 were retrieved. Result: A total of 114 surgical patients’ data were analysed, of which most were adults (72.8%), female (69.3%) and Malay (67.5%). The mean LOS was 5.90 ± 4.35 days. Pearson correlation revealed age (r = 0.309, p = 0.001) and preoperative albumin (r = -0.397, p <0.001) having a significant correlation with LOS. An independent samples T-test showed that males had significantly higher mean LOS than females (t = 2.653, p = 0.009). Surprisingly, having been seen by dietitians and being supplemented by oral nutrition supplements (ONS) had longer stay compared to groups who were not seen by dietitians and given ONS respectively (t = 4.278, p<0.001), (t = 3.111, p = 0.002). Furthermore, those with a moderate and high risk of malnutrition spent approximately 3.27 days longer hospitalized than low-risk patients (t = -2.868, p = 0.007). Conclusion: Factors that influence LOS are age, gender, preoperative albumin, seen by a dietitian, risk of malnutrition and oral nutrition supplementation.