Abstract: Weave the plain fabrics in different densities with same yarn and obtain high-count and highdensity plain fabrics with different densities after finishing processing. By testing the warp density, weft density, tightness, air permeability and shielding rate, results indicated that there was a strong negative correlation between the air permeability and tightness, and a strong positive correlation between the shielding rate and tightness. And the effect of tightness on air permeability is greater than that of visual shielding property. Therefore, more consideration should be given to the effect on the air permeability of the fabric when adjusting the warp and weft density.

Key words: warp density; weft density; tightness; air permeability; shielding rate; visual shielding property