Khitini (ing. chitin, kutoka gir. χιτών khiton "ganda, kinga") ni dutu ngumu nusu angavu inayofanya kiunzi nje ya wadudu na arithropodi wengine. Inapatikana pia katika kuta ya seli za fungi. Kikemia ni aina ya polisakaridi yaani molekuli ndefu ya kabohidrati ya (C8H13O5N)n. Chitin Product Information from China GreatVista Chemicals Archived 20 Juni 2006 at the Wayback Machine. Horseshoe Crab Chitin Research Archived 26 Juni 2009 at the Wayback Machine. Wikimedia Commons ina media kuhusu: Khitini Horseshoe Crab Chitin Research Archived 26 Juni 2009 at the Wayback Machine. Information about Chitin (Heppe Medical Chitosan) Martín-Gil FJ, Leal JA, Gómez-Miranda B, Martín-Gil J, Prieto A, Ramos-Sánchez MC (1992). "Low temperature thermal behaviour of chitins and chitin-glucans". Thermochim. Acta 211: 241–254. doi:10.1016/0040-6031(92)87023-4 .