There is a hard lump on the left side of men’s abdomen, which may be caused by fecal residue and sigmoid colon cancer. 1. Fecal matter residue: in constipated patients, too much feces accumulates in the intestinal tract, if the patient’s abdominal wall is thin, a hard lump like stripes can be touched in the left lower abdomen, which can be accompanied by pain or discomfort when pressed. It can be manifested as a hard lump on the left side of abdomen, which is painful when pressed. 2. Sigmoid colon cancer: refers to malignant tumor occurring in the sigmoid colon, with no obvious symptoms in early stage, with the progress of disease, abdominal pain, abdominal distension, change of stool habit and character, mucus blood stool, anemia, abdominal mass, weight loss and other symptoms. It can also be manifested as a hard lump on the left side of men’s abdomen hurts when pressed. There are many other causes of men’s abdominal pain on the left side of a hard lump, should be taken seriously, timely consultation, to identify the cause of the disease, and follow the doctor’s advice for further treatment or treatment.