Siku ya kimataifa ya vijana (kwa Kiingereza: World Youth Day; kifupi: WYD) ni tukio linaloandaliwa na Kanisa Katoliki kwa ajili ya rika hilo. Kila mwaka siku ya vijana inaadhimishwa ama katika majimbo tu kwenye Jumapili ya matawi, ama kimataifa katika mji fulani. Mpango huo ulianzishwa na Papa Yohane Paulo II mwaka 1985 kwa kufuata mang'amuzi yake nchini Polandi ukaendelezwa na waandamizi wake, Papa Benedikto XVI na Papa Fransisko. Misa ya kumalizia adhimisho hilo mjini Manila, Ufilipino, mwaka 1995 ilihudhuriwa na watu milioni 5. Its concept has been influenced by the Light-Life Movement that has existed in Poland since the 1960s, where during summer camps Catholic young adults over 13 days of camp celebrated a "day of community". nsymmonds (22 December 2008). Statements of Benedict XVI. Blog.beliefnet.com. Jalada kutoka ya awali juu ya 2012-09-28. Iliwekwa mnamo 5 December 2011. Yago de la Cierva, Communication on Church Events. The making of WYD Madrid 2011, Edusc, 2014. Juan Narbona, Daniel Arasa, Mass religious events as opportunities for tourism promotion.