25-30Milkweed (M) fibres have been blended with cotton (C) fibres at three different proportions and the rotor-spun yarn fabrics are produced. The comfort properties of 100% cotton and C/M blended fabrics are analysed. The fabrics have been dyed with two types of reactive dyes, namely CI Reactive Yellow 3RS and CI Reactive Red 120, and the colour strength and other calorimetric parameters of the dyeing are analysed. From the comfort properties of the fabrics, it is noticed that the air and water vapour permeabilities of C/M blended fabrics are lower than the 100% cotton fabric and decrease with the increase in milkweed proportion. The thermal conductivity of C/M blended fabrics is lower than 100% cotton fabric and decreases with the increase in milkweed proportion. The reduction in inter-yarn space and higher yarn hairiness leads to reduction in air, water and thermal conductivity values with the increase in milkweed proportion. The wickability of C/M blended fabrics increases with milkweed proportion due to the open yarn structure and hollowness of milkweed fibres. From the dyeing behaviour of fibres, it is observed that the colour strength of C/M 80/20 is higher than 100% cotton and it decreases with the further increase in milkweed blend proportion. The low cellulose percentage, higher crystalline orientation index of milkweed fibres compared to cotton results in lower colour strength values with milkweed percentage greater than 20%