Nowadays, in order to improve some of the properties of core-spun yams, a new type of core-spun yam called as dual-core has been developed. In literature, there are limited studies and hence findings about dual-core yams. Therefore, in this study, dual-core yams were produced with three different sheath fibres (viscose, cotton and cotton/Tencel blended fibres) and two different core filament linear density (50 and 70 denier) having three different yam counts (12/1 Ne, 16/1 Ne and 20/1 Ne). Woven and knitted fabrics were manufactured and yam quality parameters and some of the fabric properties such as fabric pilling behaviour, breaking and bursting strength, breaking elongation and bending rigidity were investigated. Therefore, at the end of study, it was possible to investigate the effect of sheath fibre type, yam count and core filament linear density on yam and fabric properties of dual-core yams.