When rectal cancer is combined with enlarged pelvic lymph nodes, it may suggest lymph node metastasis, which needs further examination for clarification, and pelvic inflammation can also lead to enlarged lymph nodes. Rectal cancer is a common malignant tumor of intestinal tract, besides direct metastasis and blood metastasis, lymph node metastasis will also occur, such as pelvic lymph node metastasis and inguinal lymph node metastasis. When rectal cancer lymph node metastasis occurs, it will be manifested as enlargement and morphological change of lymph nodes. In addition, when inflammatory reaction occurs in pelvis, it can also lead to enlarged pelvic lymph nodes, such as gynecological disease pelvic inflammatory disease, etc. Therefore, further examination is needed to identify whether it is enlarged lymph nodes caused by rectal cancer, and pathological examination is needed to give a definite diagnosis. If rectal cancer with pelvic lymph node metastasis is confirmed, surgery and related treatment should be performed as early as possible to avoid aggravation of the disease and affecting the prognosis of life cycle.