Hufu (Chinese: 胡服; pinyin: húfú; Korean: 호복; Hanja: 胡服; RR: hobok), also referred as Hu clothing, nomadic dress, 'barbarian' clothing or dress, or foreign dress, is a generic term which refers to any clothing which was worn in ancient China and its surrounding regions by non-Han Chinese people. This term is also used to refer to clothing of foreign origins in ancient China. The introduction of Hufu-style garments and attire in China occurred by the time of King Wuling of Zhao.

The term 'Hu' was adopted to refer to the non-Han Chinese population which could include the ancient 'Hu' northern nomadic people, such as the Xiongnu, as well as the people from the Western regions such as Sogdians, the Sasanid Persian, the Turkic people (Tujue), Uyghur (Huihe or Huihu), Tibetans (Tufan), and the Khitans (Qidan) who lived in the north and west regions of the empire.

The traditional way to distinguish between Hufu and Hanfu, Chinese clothing, is by the direction in which the garment collar closes.

Clothing style which overlaps in the front and closes to the right, known as youren (Chinese: 右衽) originated in China, and was first worn during the Shang dynasty in China. The youren collar is an important symbol of the Han Chinese, and traditionally Chinese robes and Chinese jackets must cover the right part of the body. However, the Chinese did also wear clothing which overlaps in the front and is closed on the left side, in a style known as zuoren (Chinese: 左衽). According to the Shuowen Jiezi 《說文解字》, a form of paofu, known as xi (襲), was a robe with a zuoren closure. The coat known as zhe (褶; sometimes referred as xi), typically used as part of the kuzhe, was also a xi (襲) according to the Shiming.

The use of zuoren, however, was typically associated with funeral practices. This can also be found in the chapter Sang da ji 《喪大記》of the Liji《禮記》:

"At both the dressings the sacrificial robes were not placed below the others. They were all placed with the lapel to lie on the left side. The bands were tied firmly, and not in a bow-knot [小斂大斂，祭服不倒，皆左衽結絞不紐]."

According to ancient Chinese beliefs, the only moment a Han Chinese was supposed to close their clothing in the zuoren-style is when they dressed their deceased. This funeral practice stemmed from ancient Chinese beliefs in the yin and yang theory, where it is believed that the left represents the yang aspect and stands for life, whereas the right represents the yin aspect, which stands for death. Based on this belief, the left lapel needs to be outside (i.e. youren) to indicate that the power of the yang is suppressing the yin, and was thus reserved for the clothing of living people. However, if the yin aspect surpasses the yang, which is represented by the zuoren, then this form of clothing is to be worn by the deceased. Therefore, it was taboo in ancient China for a living person to wear zuoren.

The rule of wearing youren was not always respected by the Han Chinese: for example, in the 10th century, some ethnic Han Chinese could be found wearing left-lapel clothing in some areas (such as Northern Hebei); and following the fall of the Yuan dynasty, left lapel ru continued to be worn in some areas of the Ming dynasty despite the dynasty being led by Han Chinese.