Square Enix Holdings Co., Ltd.[a] is a Japanese entertainment conglomerate and video game company best known for its Final Fantasy, Dragon Quest and Kingdom Hearts role-playing video game franchises, among numerous others. Outside of video game publishing and development, it is also in the business of merchandise, arcade/amusement facilities and manga publication under its Gangan Comics brand.

The original Square Enix Co., Ltd. was formed in April 2003 from a merger between Square and Enix, with the latter as the surviving company. Each share of Square's common stock was exchanged for 0.85 shares of Enix's common stock. At the time, 80% of Square Enix staff were made up of former Square employees. As part of the merger, former Square president Yoichi Wada was appointed the president of the new corporation, while former Enix president Keiji Honda was named vice president. Yasuhiro Fukushima, the largest shareholder of the combined corporation and founder of Enix, became chairman. In October 2008, Square Enix conducted a company split between its corporate business and video game operations, reorganizing itself as the holding company Square Enix Holdings Co., Ltd., while its internally domestic video game operations were formed under the subsidiary Square Enix Co., Ltd.

Several of Square Enix's franchises have sold over 10 million copies worldwide after 2020, with Final Fantasy selling 168 million, Dragon Quest selling 84 million, and Kingdom Hearts shipping 35 million. In 2005, Square Enix acquired arcade corporation Taito, known for games such as Space Invaders, Bubble Bobble and Darius. In 2009, Square Enix acquired British game publisher Eidos Interactive, which was absorbed into Square Enix Europe to publish titles such as Tomb Raider, Deus Ex and Just Cause. Square Enix is headquartered at the Shinjuku Eastside Square Building in Shinjuku, Tokyo, and has over 5,000 employees worldwide through its base operations and subsidiaries.