The CRH380A Hexie (simplified Chinese: 和谐号; traditional Chinese: 和諧號; pinyin: Héxié Hào; lit. 'Harmony') is a Chinese electric high-speed train that was developed by CSR Corporation Limited (CSR) and is currently manufactured by CRRC Qingdao Sifang. As a continuation of the CRH2-380 program it both replaces foreign (Japanese) technology in the CRH2 with Chinese developments and increases its top speed. The CRH380A is designed to operate at a cruise speed of 350 km/h (217 mph) and a maximum speed of 380 km/h (236 mph) in commercial service. The original 8-car train-set recorded a top speed of 416.6 km/h (258.9 mph) during a trial run. The longer 16-car train-set reached 486.1 km/h (302.0 mph).

CRH380A is one of four Chinese train series which have been designed for the new standard operating speed of 380 km/h (236 mph) on newly constructed Chinese high-speed main lines. Officially, it is the only series of the four not based on a foreign design, and although it was not produced under a technology transfer agreement, there have been accusations that it is based on unlicensed Shinkansen technology.

The other three series are CRH380B, which uses technology from Siemens, CRH380C, with technology from Hitachi, and CRH380D, with technology from Bombardier Transportation.

Development began in early 2008 during the research of the CRH2-300, which was later known as the CRH2C. CSR Corporation conducted over 1,000 technical tests across 17 specific areas, including dynamic performance, pantograph-catenary current collection, aerodynamics, and traction performance. These studies enabled CSR to develop technology that allowed for an increased maximum speed, and the findings were incorporated into the designs for the new-generation high-speed train.

The original project was named "CRH2-350". On February 26, 2008, the Chinese Ministry of Science and Ministry of Railway (MOR) signed the Agreement on Joint and Independent Innovations of China High-speed Trains. CRH2-350 is one of the most important projects of this plan, the purpose of which is the development of Chinese-designed new-generation high speed trains with continuous operating speeds of 350 km/h (217 mph), and maximum operating speeds of 380 km/h (236 mph). The next generation of rolling stock is expected to be used on the Beijing–Shanghai high-speed railway. The project officially launched in 2009, and was included in the "Eleventh Five-Year Plan"'s technology support program for developing technology and equipment for China' s high speed trains.

Designs were driven by analysis of data and operational experience from the Beijing–Tianjin high-speed rail. The Ministry of Railway completed an initial series of system and subsystem designs, then provided CSR Sifang with primary data and design. CSR presented more than 20 design variations. After further optimization, simulation and testing, the final design was published in an official conference held by Sifang on April 12, 2010 with significant changes to traction system, internal amenities and exterior carbody design. A train model was exhibited in May at the China Railway Pavilion in the Shanghai World Expo Park.

In September 2009, Ministry of Railways awarded a contract for one hundred 16-car and forty 8-car new-generation high-speed trains from CSR Sifang Locomotive & Rolling Stock in a contract worth ¥45 billion (US$6.64 billion).

According to CSR, the overall design of CRH380A reflects ten major goals.