Jiang was born into a Hakka family in Keelung, a city in northern Taiwan in 1960. During high school when he was 13, it was reported that he once wrote an essay saying that his dream career is to be the President of the Republic of China once he grow up.

He earned his bachelor's and master's degree in political science from National Taiwan University (NTU). He did his doctoral degree in political science from Yale University, United States in 1993. Upon graduation, he returned to Taiwan to become a professor at NTU.

MOI officially launched the "1996 Hotline of Interior Affairs" in November 2011 after three months operation trial. Speaking at the press conference, Jiang said that the MOI is in charge of almost everything in people's daily life, ranging from marriage and birth registration, various social welfare and subsidies provider, petition Service, corruption reporting, housing transfer registration and emergency reporting. In order to make their Service more efficient and more convenient to people, MOI has merged some of their Service hotline into one single number.

Jiang entered politics for the very first time in 2008 when he was appointed as the Minister of Research, Development and Evaluation Commission of the Executive Yuan on 20 May 2008.

In December 2009, Jiang said that officials from Ministry of the Interior and Ministry of Justice should ensure justice and fairness in ROC administrative electoral process by avoiding stumping on the candidates. In March 2010, Jiang said that Taiwan will have seven kinds of local elections being held all in one day starting in 2014.

In July 2012, Jiang said that the Executive Yuan is mulling immigration and population policy in order to attract foreign talents, boost human capital and improve Taiwan's competitiveness. He added that policies from various ministries will be integrated so that this regulation change won't affect much to the current local employment.

In early May 2013, Jiang said that he hates corruption and wish to have all of his Executive Yuan officials free from such involvement. He requested ROC Minister of Justice Tseng Yung-fu to look into any unsuitable officials for their position. He requested not only the heads of government to maintain their integrity, but also all of the other officials working under them. The move came after several corruption cases involving Cabinet Secretary-General Lin Yi-shih and Kuomintang Taipei City Councilor Lai Su-ju.

In September 2014 ahead of independence referendum of Scotland from the United Kingdom, Jiang stated that there is no need for the ROC, as an independent nation, to hold an independence referendum. He denied that there was a similar comparison between Taiwan and Scottish referendum, adding that keeping the ROC as an independent and sovereign state is the top priority for the government to do.