Hair is oily and dry may be bad habits, vitamin B deficiency, sebaceous gland secretion, dry syndrome and other reasons, need to address the cause of the medication or to keep the skin clean and so on. 1. Bad habits: long time not wash hair, long time in dusty environment, long time stay up late and lack of sleep, eat a lot of spicy and greasy stimulating food and other physiological factors may cause hair dryness and lack of water, excessive secretion of oil and the above symptoms. 2. Vitamin B deficiency: Vitamin B is involved in the body’s metabolism of a variety of substances, energy synthesis and enzymatic reactions and other processes, the lack of vitamin B may appear keratitis, seborrheic dermatitis and other diseases, so the above symptoms will occur. You need to take vitamin B tablets and eat more green vegetables and fruits. 3. Excessive sebaceous gland secretion: excessive androgen levels, heredity, infections and other factors lead to exuberant sebaceous gland secretion in the scalp, so this symptom will appear. You can take finasteride, spironolactone and other drugs to reduce the production of androgens, or topical calcium-modulated phosphatase inhibitors such as tacrolimus ointment, etc., pay attention to hair and scalp cleanliness. 4. Dry Syndrome: Due to the autoimmune system produces antibodies wrongly attacking its own salivary glands, lacrimal glands, digestive glands, sebaceous glands and other glands, resulting in gland synthesis and secretion dysfunction, so the hair will be dry and greasy. Prednisone, methotrexate, leflunomide, hydroxychloroquine and other drugs can be applied. Dry and oily hair may be related to a variety of factors, it is recommended to go to the hospital in time to find out the cause, symptomatic treatment, medication should be used in accordance with medical advice.