日立（HITACHI），是来自日本的全球500强综合跨国集团，1979年便在北京成立了第一家日资企业的事务所。日立在中国已经发展成为拥有约150家公司的企业集团。

HITACHI日立事业领域涉及能源系统、保障人们安全舒适出行的铁路等交通系统，运用大数据进行创新的信息系统，以及通过健康管理、诊断、医疗技术等提供健康生活的医疗保健等等。

日立用创新回应社会所面临的课题。HITACHI日立在2015年度（2015年4月1日至2016年3月31日）的合并销售额达到100,343亿日元，员工约335,000名。HITACHI日立作为社会创新事业的全球领军者，开展的业务涉及电力、能源、产业、流通、水、城市建设、金融、公共、医疗健康等领域，通过与客户的协创提供优质解决方案。中国是HITACHI日立最为重要的市场之一。截止到2015年度末，HITACHI日立集团在中国拥有180家集团企业，正式员工约47,800名，在中国市场的销售额达到10, 555亿日元，约占HITACHI日立集团全球总销售额的10%。HITACHI日立致力于通过“社会创新事业”为中国的社会发展及产业升级做出积极贡献。

Hitachi, Ltd. (株式会社日立製作所 Kabushiki-gaisha Hitachi Seisakusho) is a Japanese multinational conglomerate company headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (Hitachi Gurūpu) and forms part of the DKB Group of companies. Hitachi is a highly diversified company that operates eleven business segments: Information & Telecommunication Systems, Social Infrastructure, High Functional Materials & Components, Financial Services, Power Systems, Electronic Systems & Equipment, Automotive Systems, Railway & Urban Systems, Digital Media & Consumer Products, Construction Machinery and Other Components & Systems.

Hitachi is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225 and TOPIX indices. It is ranked 38th in the 2012 Fortune Global 500 and 129th in the 2012 Forbes Global 2000.

Hitachi was founded in 1910 by electrical engineer Namihei Odaira in Ibaraki Prefecture. The company's first product was Japan's first 5-horsepower induction motor, initially developed for use in copper mining. Odaira's company soon became the domestic leader in electric motors and electric power industry infrastructure.

Hitachi began as an in-house venture of Fusanosuke Kuhara's mining company in Hitachi, Ibaraki. Odaira moved headquarters to Tokyo in 1918. Long before that, he coined the company’s toponymic name by superimposing two kanji characters: hi meaning “sun” and tachi meaning “rise”. The young company's national aspirations were conveyed by its original brand mark, which evoked Japan's imperial rising sun flag.

World War II and its aftermath devastated the company. Many of its factories were destroyed by Allied bombing raids, and after the war, American occupational forces tried to disband Hitachi altogether. Founder Odaira was removed from the company. Nevertheless, as a result of three years of negotiations, Hitachi was permitted to maintain all but 19 of its manufacturing plants. The cost of such a production shutdown, though, compounded by a three-month labor strike in 1950, severely hindered Hitachi's reconstruction efforts. Only the Korean War saved the company from complete collapse. Hitachi and many other struggling Japanese industrial firms benefited from defense contracts offered by the American military. Meanwhile, Hitachi went public in 1949.

Hitachi America, Ltd. was established in 1959. Hitachi Europe, Ltd. was established in 1982.

In March 2011, Hitachi agreed to sell its hard disk drive subsidiary, HGST, to Western Digital (WD) for a combination of cash and shares worth US$4.3 billion. Due to concerns of a duopoly of WD and Seagate Technology by the EU Commission and the Federal Trade Commission, Hitachi's 3.5" HDD division was sold to Toshiba. The transaction was completed in March 2012.

Hitachi entered talks with Mitsubishi Heavy Industries in August 2011 about a potential merger of the two companies, in what would have been the largest merger between two Japanese companies in history. The talks subsequently broke down and were suspended.

In October 2012, Hitachi agreed to acquire the United Kingdom-based nuclear energy company Horizon Nuclear Power, which plans to construct up to six nuclear power plants in the UK, from E.ON and RWE for £700 million.

In November 2012, Hitachi and Mitsubishi Heavy Industries agreed to merge their thermal power generation businesses into a joint venture to be owned 65% by Mitsubishi Heavy Industries and 35% by Hitachi. The joint venture began operations in February 2014.