A rolling blob felt on the side of the neck may be an enlarged lymph node, a sebaceous cyst of the neck or a lipoma of the neck. 1. Swollen lymph nodes: When infection by pathogenic microorganisms leads to chronic inflammation, such as acute cellulitis, lymphocytes fight off pathogens, resulting in enlarged lymph nodes. The lymphatic tissue in the neck is located under the skin and has a soft, sliding texture. Therefore a rolling blob may be an enlarged lymph node. 2. Neck sebaceous cysts: Sebaceous gland secretion is exuberant, not paying attention to cleanliness leads to glandular duct blockage, glandular duct secretion retention caused by sebaceous gland cysts, can be pushed when squeezed, easy to secondary skin redness, swelling, pain and other symptoms. 3. Neck lipoma: benign tumor formed by proliferating adipose tissue, surrounded by connective tissue, with clear boundary and regular shape, mostly located in the subcutaneous area, which can be slid when touched. If you touch the small ball in the neck that can slide and affect your daily life, you need to consult a doctor for neck ultrasound to clarify the cause of the disease, and under the guidance of the doctor to carry out the treatment.