McKrittick-Wheelock syndrome refers to a condition characterized by a large rectal mass accompanied by excessive mucoid discharge and associated electrolyte imbalances, including hyponatremia and hypochloremia. This is a benign condition that can unexpectedly lead to serious illness in patients, making it essential for all clinicians to be aware of. We present the case of an 80-year-old female presented with a 4-year history of secretory diarrhea, hematochezia, enlarging fleshy rectal mass with copious mucoid discharge associated with hyponatremia and hypochloremia. Physical examination revealed a polypoid rectal mass secreting copious mucoid discharge with a 2cm base of stalk prolapsing 4cm FAV. The patient underwent rectal excision via trans-anal approach leading to resolution of symptoms. Postoperatively, the patient made a good recovery and was discharged. During follow-up, there was no recurrence of secretory diarrhea. Additionally, the dizziness and other symptoms had resolved. This case emphasizes the importance of recognizing McKittrick-Wheelock syndrome (MWS) when faced with a rectal mass presenting alongside chronic secretory diarrhea and associated electrolyte disturbances. Despite its rare occurrence, clinicians should consider this diagnosis in patients with a rectal mass to avoid delayed treatment and prevent serious complications.