Guanzi is a double-reed musical instrument, which has a very long history. It is developed in the ancient Persia, which is the present Iran. In ancient China, people called it "bili" or "luguan". About more than two thousand years ago, guanzi had already been very popular in the Xinjiang region. Later, it was introduced into the mainland and the performing skills were greatly improved. Today, guanzi has been frequently played by the northern people.

The instrument is loud with a clear and bright tone. It carries with itself a strong countryside flavor. The structure is very simple; it is made up of only three parts. It is often performed in solo, concert and accompaniment. In some music of the northern China, guanzi has played a very important role. The performance skills are various, such as roulade and glissandi and some unique skills. While performing, performers can depend on the degree of lip-rounding to imitate the human voice and the animal sound. There are various kinds of guanzi, such as the double-reed guanzi, and those of different sizes.

The solo below played by guanzi is smooth and relaxing. Such music can often be heard in the operas when the characters are changing their clothes or walking down the streets.