Introduction Free muscle transfer for facial reanimation requires the sacrifice of motor nerves and muscles, which inevitably leads to donor site morbidity. To overcome this, the authors performed the interfascicular nerve splitting technique during neurovascular latissimus dorsi flap harvest. The aim of this study was to examine the efficacy of our interfascicular nerve splitting technique through the evaluation of donor site morbidity. Methods Records of patients in who the free latissimus dorsi flap was employed with the interfascicular nerve splitting technique between 2012 and 2016 were reviewed. Postoperative donor site morbidity was evaluated using electromyography, nerve conduction studies, and the Quick-Disabilities of Arm, Shoulder, and Hand questionnaire (QuickDASH). Results A total of 13 patients were analyzed. Grades from the electromyography and nerve conduction study were not significantly different between the donor site and contralateral side (0.42±0.51 and 0.08±0.28, respectively, P = .073). QuickDASH scores showed different results over time. Preoperative QuickDASH scores averaged 1.57±2.34. At postoperative 6 months, the average QuickDASH score was 8.74±4.62, which was significantly different from the preoperative average (P = .001). At postoperative 12 months, QuickDASH scores averaged 2.62±3.19, which was an improvement from the postoperative 6-month score. However, the improvement was not significantly different from the preoperative score (P = .059). Conclusion The present study showed that interfascicular nerve splitting could minimize donor site morbidity. Moreover, our results suggest that the split nerve can function as a donor nerve. Our novel method could be a valuable option for minimizing donor site morbidity during facial reanimation surgery.