Colorectal cancers (CRC) are predominantly adenocarcinomas, accounting for the majority of cases. Rarer variants include neuroendocrine carcinoma, squamous cell carcinoma, adenosquamous carcinoma, spindle cell carcinoma, and undifferentiated carcinomas. Rectosigmoid squamous cell carcinoma is an exceedingly rare diagnosis, with only 150 cases reported in medical literature. We present a case of rectosigmoid squamous cell carcinoma (SCC) in a 50-year-old female who presented in the emergency department with left lower abdominal pain, fever, non-passage of stools, and ?atus for two days. The diagnosis was challenging due to its unusual location and atypical presentation. The patient underwent rectosigmoidectomy, and the specimen was sent for histopathological examination. After a thorough gross and microscopic examination, the diagnosis of moderately differentiated squamous cell carcinoma of the rectosigmoid colon was made. This case highlights the importance of considering rarer malignancies in the differential diagnosis of colorectal malignancies. A thorough gross and microscopic examination is needed to diagnose rarer malignancies of the colorectal region. A multidisciplinary approach is required for accurate diagnosis and treatment