Filling of lines can be done by hyaluronic acid filling, fat filling, collagen filling and so on. If patients have this need, it is recommended to go to a regular medical cosmetology organization. Under the guidance and advice of the doctor to choose the appropriate treatment method. 1. Hyaluronic Acid Filling: Hyaluronic Acid is injected into the sunken areas of the frown lines by injection method to fill and smooth out the frown lines. Usually, the effect can be maintained for 6 to 12 months. The advantages are short operation time, high safety, little pain and reversible effect. The disadvantage is that it needs to be injected regularly and the effect is not long-lasting. 2. Lipo-filling: Through autologous lipo-filling, fat is extracted from parts of the body where there is a lot of fat. After special processing into pure fat particles, it is injected and transplanted to the depressed areas of the lines. The effect can usually be maintained for a long time, and the advantages are that there is no rejection reaction and less trauma. The disadvantage is that there will be a certain degree of absorption after filling, which requires multiple injections. 3. Collagen Filling: Collagen is injected into the lines to improve the depression of the lines. The effect can be maintained for 6 to 12 months. The operation time is short, less traumatic and less painful. There are many ways to fill the lines, and it is recommended that patients go to a regular cosmetic medical institution to reduce medical risks.