Yu-Gi-Oh! Official Card Game is the version of the Yu-Gi-Oh! card game manufactured by Konami. It is played mainly in Japan, South Korea, and other parts of Asia including Hong Kong, Taiwan, Philippines, Malaysia, Singapore and Thailand. The OCG used to be printed exclusively in Japanese (JP), Korean (KR). It has previously been printed in English (referred to as Asian-English); despite being part of the OCG, Asian-English cards have "Yu-Gi-Oh! Trading Card Game" printed on their backings, though with a different logo. In the past there have been 3 different Chinese prints of cards, including two "Blue-Eyes White Dragon"s and one "Dark Magician", though they were only for promotional purposes. Starting from Duel Starter Deck and onward, the OCG has started to be officially printed and distributed in Traditional Chinese (TC), and will now follow a regular release schedule.; additionally, starting from Duelist Alliance, Japanese cards distributed outside Japan are considered "Japanese-Asian" (JA) cards.
TCG cards are not legal in OCG tournaments. Due to Japanese, Asian-English and Korean cards having different backings, if a player chooses to use a mixture, they must use protective sleeves that cover the back of the cards.
OCG tournaments are divided into three classes: Expert, which has no age restriction, Regular: for secondary school students and Challenge, for primary school students.
Japanese cards (JP) used to be distributed in all over Asian territories, but now exclusively in Japan by Konami of Japan. Korean cards are only printed in South Korea, and distributed by Daewon Media. Asian-English, Japanese-Asian and Traditional Chinese cards are distributed in other parts of Asia by Konami of Hong Kong.