In current scenario, the consumption of the sportswear has been increasing tremendously. It is very important to produce sportswear with more comfort, functionality and cost effective. To obtain these, different fibres and techniques have been adopted to achieve the above properties. In this work, bi-layer knitted fabric has been produced in interlock jacquard knitting machine with inner layer as polyester and outer layer as cotton.The aim of this project is to develop polyester/ cotton bi-layer knitted fabric with different combinations and to study the physical aspects and comfort aspects such as wetting, wicking, water absorbency, dryness, moisture vapour transfer, thermal conductivity and air permeability based on objective and subjective evaluation. Based on the test results sportswear of combinations like 40s/150D, 40s/80D, 60s/150D, 60s/80D and 20s/150D are ranked. From this work it is recommended that bi-layer knitted fabrics can be used in sports like volleyball, athletics, cricket and foot ball for better comfort and performance of the sports person.