If there is a bone protruding from the forehead, it may be a local bony mass such as bone cyst or osteochondroma, or a local lipoma. If a lipoma is considered, a local ultrasound examination is available. If it is considered to be a bone mass, CT and 3D reconstruction of the skull should be done to determine the result and deal with it accordingly. If it is a lipoma or bone cyst of the skull, it can be followed up and observed when it is small. If it is large, it can be removed surgically, and after surgery, routine pathological examination is needed to exclude malignant masses.