The absorption time of hyaluronic acid can not be generalized, with the type of hyaluronic acid, injection site and level and other factors, water light injection with small molecule hyaluronic acid is generally 1-3 months to be absorbed, filler class of large molecule hyaluronic acid will be absorbed in 6-12 months. Hyaluronic acid is the commonly used material for facial filler, it can exist normally in the human body, its tissue compatibility is very good, high security, and the effect is reversible, dissatisfaction can be dissolved by dissolving enzyme, and there is hyaluronic acid enzyme in the body, hyaluronic acid can be gradually degraded and absorbed. There are three kinds of hyaluronic acid: large molecule, medium molecule and small molecule. Large molecule hyaluronic acid can keep longer time, small molecule hyaluronic acid can keep shorter time; the deeper the level of hyaluronic acid is injected, the slower it is absorbed; the lower the activity of the injected part is, the longer its lasting effect is. Generally speaking, small molecule hyaluronic acid can be absorbed in 1-3 months at the earliest, and the metabolism time of large molecule hyaluronic acid is 6-12 months. It is recommended that patients in need of hyaluronic acid injections should go to regular hospitals and choose the best treatment plan under the doctor’s guidance in order to minimize the occurrence of adverse reactions and achieve satisfactory treatment results.