In 1988 Zhang returned to work for the Ministry of Aerospace Industry and later joined China Academy of Launch Vehicle Technology, the birthplace of China's Long March rocket. He showed exceptional talent at CALT and was credited with the 1990 launch of the AsiaSat 1 satellite for the American company Hughes Satellite Systems. It marked the first time for the Long March rocket to successfully launch a foreign satellite. After the success with AsiaSat 1, Zhang was tasked with developing the Long March 2 rocket for China's human spaceflight program. He became the deputy director of CALT in 1996, and the vice-manager of the newly established China Aerospace Science and Technology Corporation in 1999. In 2001 he was appointed president of CASC, and starting in February 2002 he concurrently served as deputy chief commander of the Shenzhou program. In October 2003 Shenzhou 5 completed China's first ever human spaceflight mission, and two years later two more astronauts safely returned to earth after a five-day spaceflight on Shenzhou 6. In August 2007 Zhang was appointed chairman of the Commission for Science, Technology and Industry for National Defense, becoming one of the youngest persons to hold a minister-level post in China. He guided the merger of COSTIND with the Ministry of Industry and Information Technology in 2008. He also concurrently served as head of the Chinese Lunar Exploration Program. In 2008 Zhang was appointed chairman of the Commercial Aircraft Corporation of China, a state-owned enterprise that was newly established to develop China's own jumbo jets. In 2009, he drew international attention after being named one of China's 40 most powerful people by BusinessWeek.
Political career
Zhang joined the Communist Party of China in December 1992. In 2002, less than ten years after he joined the party, he was appointed to the 16thCentral Committee of the CPC, the party's top authority. At age 41 he was the youngest full member of the committee. He has subsequently been elected to full memberships of the 17th and 18th Central Committees. In August 2011 Zhang left Comac and was appointed acting governor of Hebei Province, replacing Chen Quanguo, who had been promoted to Party Secretary of Tibet Autonomous Region. In January 2012 he was officially elected by the Hebei Provincial Congress as governor, and reelected in January 2013. Zhang was one of the earliest examples of rocket scientists taking on major political posts in China, a trend that intensified following Xi Jinping's ascension to the General Secretary of the Communist Party of China in 2012, with many "space alumni" joining government ranks thereafter. Zhang was transferred to Heilongjiang to serve as party secretary in April 2017, becoming the fourth official born after 1960 to assume a provincial party secretary post.