Abstract: For improving the ultraviolet protection properties of polyester fabrics for summer apparels,this article adds functional anti-UV master batch additive to polyester filaments which are used to weave a lot of fabric samples,and testing of samples are conducted.The effect of structural changes such as fabric count and weave,as well as the content of master batch additive in the material on the ultraviolet protection properties of polyester fabrics is investigated.The results show that the ultraviolet protection properties of polyester fabrics is improved with increasing the content of functional additive,fabric count and float of weave,especially the fabric with backed weaves.