Forehead wrinkles may be caused by excessive contraction of the frown muscle, skin laxity and other factors. 1. Excessive contraction of the frowning muscle: frequent frowning movements can lead to the emergence or aggravation of the symptoms of wrinkles, and for a long time, muscle memory will be formed and dynamic wrinkles will appear. 2. Skin laxity: ageing, excessive weight loss, malnutrition and other factors may lead to loss of collagen at the forehead, skin laxity, and the gradual formation of static ChuanZi lines. Normally, we should keep a relaxed and happy mood, reduce the expression that is easy to form ChuanZiLin, and when ChuanZiLin has been formed, we can go to a professional and formal medical institutions, and carry out relevant treatments under the guidance of the physician, such as photoelectricity treatment, botulinum toxin injection, hyaluronic acid injection, and injection of autologous fat particles, etc., to improve the symptom of ChuanZiLin.