Casual clothing is a new popular clothing category name in modern times, and it is a kind of sportswear style clothing. Casual clothes are characterized by long-term exposure to sunlight and sweat erosion, sweat absorption and breathability, durable wear-resistant color and relaxed and comfortable shape. With the popularity of fitness craze in various countries, casual clothes will rise. Casual clothing refers to clothes worn in casual occasions. The so-called leisure occasion is the time and space for people to engage in leisure activities in leisure places besides official duties and work. Such as home, fitness, entertainment, shopping, tourism and so on. They are all leisure activities. Wearing casual clothes pursues comfort, convenience and naturalness, giving people a feeling of freedom.