There are many reasons why the upper abdomen feels hard like there is a lump inside, such as the growth of the abdominal wall, the growth of the abdominal wall muscle mass, the growth of the abdominal cavity mass and so on. 1. Abdominal wall growths: such as sebaceous cysts, fibromas, lipomas, skin papillomas, etc., can lead to the phenomenon that the upper abdomen feels hard like there is a lump inside. 2. Abdominal wall muscle growths: abdominal muscles, if there is rhabdomyosarcoma, can also lead to the phenomenon of hardness in the upper abdomen, which needs to be clearly diagnosed by CT. 3. Abdominal growths: if there are tumors in the abdominal cavity of the upper abdomen, it will also lead to hard lumps in the upper abdomen, such as malignant tumors of the stomach, malignant tumors of the liver and biliary system, malignant tumors of the intestinal tract, and so on. There are many reasons why you may feel a hard lump in your upper abdomen, and it is recommended that you go to the hospital in time to complete the examination and take standardized treatment according to the doctor’s instructions, so that you can’t ignore the symptoms and take them lightly.