An overview of the modern demodicosis diagnostics methods and in-house demodicosis diagnosis with intravital laser scanning confocal microscopy effectiveness studies. The study included 60 patients with acne and rosacea, complicated demodicosis, 60 patients with acne and rosacea and no demodicosis, and 30 healthy volunteers. All the patients underwent skin scraping, eyebrows and/or eyelashes hair removal and confocal laser-scanning microscopy. the advantages of confocal laser-scanning microscopy in vivo in comparison with conventional methods of research are shown.