Halogen derivatives of selected 3-benzofurancarboxylic acids were prepared using 6-acetyl-5-hydroxy-2-methyl-3-benzofuranocarboxylic acid as starting material. (1)H-NMR spectra were obtained for all of the synthesized structures, and for compound VI, an X-ray crystal structure was also obtained. All derivatives were tested for antimicrobial activity against a selection of Gram-positive cocci, Gram-negative rods and yeasts. Three compounds, III, IV, and VI, showed antimicrobial activity against Gram-positive bacteria (MIC 50 to 200 microg/mL). Compounds VI and III exhibited antifungal activity against the Candida strains C. albicans and C. parapsilosis (MIC-100 microg/mL).