This paper has focused on moisture management (MMT) and air permeability properties of fabrics produced from linen (100%) and linen-polyester yarns (80% polyester and 20% linen) at different weft densities. In the experimental study, eighteen different types of fabrics composed of six different weft yarns with three levels of weft density (weft density of 8,10 & 12 pick/cm for 100% linen fabrics and 14,16,18 pick/cm for polyester-linen fabrics) were selected in order to determine the influence of weft density and yarn structural parameters (number of yarn folds) on moisture management as well as air permeability properties. The following weft yarns were selected: 104/1 tex, 104/2 tex & 104/3 tex for 100% linen and 41/1 tex, 41/2 tex & 41/3 tex for 80% Polyester - 20% linen fabrics, whereas the warp yarn was constant - 50/1 tex 100% linen for all fabric types. Satin type fabrics were subjected to moisture management tests and air permeability tests as well. According to test results, it was determined that some of the moisture management (wetting time, absorption rate (%/s) and one-way accumulative transport index of the fabrics' top surfaces and bottom surfaces) and air permeability properties were significantly affected by the number of yarn folds and the weft density at a 0.05 significance level.