Core-spun yarn is generally made of synthetic fiber filaments with good strength and elasticity as core filaments, and spun yarns made of cotton, wool, viscose and other short fibers twisted together. The core-spun yarn has the excellent properties of the filament core yarn and the outer staple fiber. The more common core-spun yarn is polyester-cotton core-spun yarn, which uses polyester filament as the core yarn and is outsourced with cotton fiber. There is also spandex core-spun yarn, which is a yarn made of spandex filament as the core yarn and other fibers. The knitted fabric or jeans material made of this core-spun yarn stretches freely and fits comfortably when worn.

Its main purpose is to strengthen the cotton canvas, and maintain the water repellency of cotton fiber when exposed to water expansion, and use polyester to have tensile resistance, tear resistance and shrinkage resistance when damp in the rain. At this stage, the core-spun yarn has developed into many types, which can be summarized as follows: short fiber and short fiber core-spun yarn, chemical fiber filament and short fiber core-spun yarn, chemical fiber filament and chemical fiber filament core-spun yarn. At present, more core-spun yarns are generally made of chemical fiber filaments as the core yarn, which are outsourced with various short fibers to form a unique structure of core-spun yarns. Its core yarn commonly used chemical fiber filament polyester filament, nylon filament, spandex filament and so on. Outsourcing staple fibers are cotton, polyester, polyester, nylon, acrylic and wool fibers.