Small bumps on the lower left side of the breast may be caused by skin problems or mammary gland problems, there is nothing should be based on the specific circumstances. 1. Skin problems: if skin allergies, acne, sebaceous cysts, lipomas and other conditions will appear on the lower left side of the breast pimples, to clarify the conditions that cause skin allergies, to exclude allergens, sebaceous cysts and lipomas can be used to surgically remove, this is generally not a serious situation, through effective treatment can be cured. 2. Breast problems: small lumps on the lower left side of the breast may be due to breast occupancy, such as hyperplastic nodules, breast fibroids or malignant tumors, etc. If hyperplastic nodules, breast fibroids are not serious, they can be surgically excised or followed up on a regular basis, and if they are malignant tumors, they need a combination of surgical excision and radiotherapy, which is a serious situation. Small lumps on the left lower side of the breast may also have other causes, it is recommended to go to the regular hospital for examination, to clarify the cause of the disease, according to the cause of the treatment or observation.