The aim of this work was to evaluate the impact of different extraction methods on bioactivity of the extracts from nettle (Urtica dioica L.) leaves and fennel (Foeniculum vulgare) seeds. Extracts were obtained by using accelerated solvent extraction (ASE), microwave assisted extraction (MAE) and heat reflux extraction. Total phenolic content (TPC) was determined and ranged from 504 ± 26 to 3301 ± 171 mg GAE/100 g dw in nettle leaves extracts and from 237 ± 10 to 860 ± 26 mg GAE/100 g dw in fennel seeds extracts. Phenolic profile analyses were carried out by UPLC-MS/MS. In total, 27 different compounds were identified in nettle leaves extracts, among those cinnamic acid and kaempferol were far the most abundant in all the extracts while kaempferol-3-O-glucuronide was identified as the most dominant among 21 compounds found in fennel seeds extracts. ASE proved to be optimal method for the extraction of bioactive compounds from nettle leaves, while classical heat reflux for fennel seeds, for both using 30 % acetone as a solvent. Based on the optimal extraction conditions, new extracts were prepared for which antioxidative potential (DPPH, FRAP) and antimicrobial activity using microdilution method were determined. Nettle leaves extract showed both, better antioxidative and antimicrobial activity, compared to fennel seeds extract, which correlated also with TPC values. Both extracts had antimicrobial effect on P. fragi (MIC = 0,5 mg/mL for nettle leaves extract and MIC = 2 mg/mL for fennel seeds extract) while only nettle leaves extract had an inhibitory effect against S. aureus (MIC = 2 mg/mL). Other bacteria and yeasts tested were not sensitive to the extracts.