Whenever summer comes, “sun protection” is mentioned on the agenda. Previously, mothers only pay attention to their own sun protection, but now many mothers already know that sun protection for babies is more important. Although the skin damage caused by each UV exposure is mild and can be asymptomatic, the accumulation of years will gradually lead to a series of irreversible changes in the skin, accelerating skin aging and even leading to skin cancer. Since our lifetime exposure to sunlight is mainly in childhood, and children spend three times more time in the sun than adults, it is said that the aging rate of skin is determined before the age of 18. If we start to pay attention to sun protection from childhood until the age of 18, the chances of developing skin cancer in the future will be significantly reduced.