Rectal melanoma is generally an aggressive disease that has a poor overall 5-year survival rate, disease-free survival, and median survival period [6, 17–19]. More than half of the patients were found with regional lymph node metastasis at the time of diagnosis, and about 30% of the patients had metastasis to a distant location (e.g., lung, liver, bone, and brain) [20, 21]. The rectal melanoma surgical guideline is without consensus. Moreover, APR surgery had been regarded as the choice which performed a better margin-negative resection to control the lymphatic spread and local recurrence [22–24]. However, the inconvenience of colostomy and high morbidity rate, as well as functional limitations after APR, reduced the patients' quality of life [25, 26]. In recent years, WLE has been gradually adopted as an alternative option because of its better functional performance, less invasiveness, and freedom from stoma than APR surgery[17, 26]. In addition, APR had a lower recurrence rate in local areas than WLE surgery, but no difference was noted in the 5-year survival rate in the recent study [9, 10, 17]. Therefore, the choice for surgery needs to consider the morbidity of the surgery and the patient’s quality of life. Therefore, WLE may be another choice considering the patient’s age, comorbidities, symptom control, and quality of life. The recent meta-analysis by Smith HG et al. reported that WLE with regular surveillance for local recurrence may be recommended as the primary strategy in most patients [27]. More studies revealed that WLE combined with adjuvant RT could not only reduce local recurrence than WLE alone but avoid the functional compromise compared with APR to solve the disadvantage of high recurrence in patients after WLE [9, 14]. Furthermore, sphincter-sparing WLE with RT had a similar local recurrent rate as APR [11, 15]. Moreover, Nusrath et al. [28] revealed that the better survival for rectal melanoma had been corrected using many factors, including the tumor size of < 2 cm and margin-negative resection without lymphovascular or perineural invasion. Debulking operation was performed first to decrease tumor volume to relieve symptoms and achieve consequent treatment with RT and WLE. In this case, RT and WLE not only had a striking response to residual tumor shrinkage but achieved margin-negative resection without severe side effects. In summary, no consensus exists on rectal melanoma treatment. In addition to traditional surgery and RT, immunotherapy is recently developing as an option [29, 30]. In conclusion, the current study presented a case with stage II rectal melanoma with a complete response by combining debulking surgery, RT, and WLE. For rectal melanoma that cannot be completely resected at the beginning and accompanied by bleeding symptoms, combining debulking surgery, RT, and WLE may be viable alternatives to provide the success rate of negative resection margins, lowered local recurrence rate, less medical cost, and better quality of life. However, a large-scale case study should be considered to validate its variability.