Kayin

Kayin can refer to:
 * Kayin State, an administrative division of Myanmar (Burma)
 * Kayin or Karen people, a minority ethnic group in Myanmar
 * Kayin, Iran, a village in Kerman Province, Iran
 * alternative spelling for Cain
 * Kayin Amoh, a character in the Battle Arena Toshinden fighting game series
 * Kayin, alias of the creator of the indie video game I Wanna Be The Guy