In this dissertation, the effect of cold plasma treatment on the comfort properties of P/C blend fabric has been studied in a low pressure plasma reactor. The plasma treatment was conducted on the samples of 65% polyester and 35% cotton blend fabric using argon, oxygen and air, separately, as well as mixtures of O2/HMDSO, N2/HMDSO, H2O/HMDSO and HMDSO monomer alone as working gases. Special attention was given to oxygen plasma due to its wide application for various textile/polymer materials. Due to this reason, the Taguchi method was used to design, analyze and optimize the oxygen plasma process. Other plasma parameters including working pressure, discharge power, duration of treatment and flow rate were also considered. The various comfort properties of plasma treated and untreated P/C blend fabric have been studied. In particular, thermal comfort such as, water vapor, air permeability, thermal resistance and wickability as well as tactile comfort including hand-feel and electro-physical properties were investigated. As the results showed that the oxygen plasma treatment had a positive effect on the thermal comfort and resistivity properties of P/C the blend fabric.