**Abstract**

*Cannabis sativa L.* and *Linum usitatissimum L.* belong to fibrous plant family delivering textile fibers located in their bast of stalk. This chapter covers discussion about flax and hemp fibers properties and processing based on authors' finding and available literature. The authors will present research on flax and hemp fibers bioactivity in relationship with their chemical composition, which is strongly related to the selected method of fiber processing, including methods of fiber extraction in light of their effect on fibers antioxidant and antibacterial activity. Human-ecological features of linen/hemp textiles, including clothing effect on human physiology, are described. The case study of functional clothing preparation based on the bioactivity of bast fibers will be presented. This chapter delivers knowledge about complex factors of human-ecological performance of flax and hemp, which have a significant effect on the improvement of human life, including comfort, well-being, and healthsupporting performance. The environmental approach of bast fibers in terms of contribution to green planet protection is shortly discussed. Collected literature and authors' findings allowed to prove the positive effect of bast fibers textiles on the improvement of human life in terms of everyday wearing of clothing as well from the viewpoint of environmental impact, which is in line with the European Green Deal strategy.

**Keywords:** flax, hemp, fiber processing, fiber properties, bioactivity, antioxidant activity
