Thanathorn was born and raised in Bangkok, the second child of five. His mother, Somporn Juangroongruangkit, is the current President and CEO of the Thai Summit Group, taking over the company from Thanathorn’s father, Pattana Juangroongruangkit, after his death in 2002. Pattana founded the Thai Summit Group in 1977. The Juangroongruangkit family also owns a large stake in the Thai media conglomerate Matichon Publishing Group.
Upon starting his political career, Thanathorn resigned from the Matichon board and Thai Summit Group.
Thanathorn’s uncle, Suriya Juangroongruangkit, is a Thai politician who served as Minister of Transport of Thailand between 2002 and 2005. Suriya is currently one of the leaders of Phalang Pracharat, the most prominent pro-junta party
Thanathorn attended the Triam Udom Suksa School in Bangkok. After graduating from high school, Thanathorn obtained a joint-honours Bachelor of Engineering (B.Eng.) in Mechanical Engineering from Thammasat University and the University of Nottingham. During this time, he became President of the Thammasat University Students Union in 1999, and was later named deputy secretary-general of the Students Federation of Thailand. He later decided to pursue his interest in social and economic issues and obtained three master’s degrees: one in Political Economy from Chulalongkorn University, one in Global Finance from Stern School of Business, New York University and one in International Business Law from the University of St. Gallen.
Throughout his studies, Thanathorn was involved with various charities and NGOs calling for social and economic reforms in Thailand, including Friends of the People and the Assembly of the Poor. During this time, Thanathorn campaigned for the land and compensation rights of villagers affected by the Pak Mun dam in the Ubon Ratchathani Province. 
His family also expressed serious concern about Thanathorn’s student movement activities. It is disclosed in several interviews that Thanathorn has been in conflict with his uncle, Suriya Juangroongruangkit, since he was young mainly due to their disagreement regarding the Trans Thai-Malaysia Gas Pipeline Project. Thanathorn believes the construction of this dam exemplified the government unaccountability and crony-capitalism that peaked with the 1997 economic crisis.
After completing his studies, Thanathorn set out to pursue a career with the United Nations, and was offered a position as a development worker for the UN in Algeria. However, Thanathorn was forced to abandon his plans when his father, Pattana Juangroongruangkit, was diagnosed with cancer. Following his father’s death in 2002, Thanathorn returned to Thailand and assumed leadership of the Thai Summit Group at just 23 years old.
Under Thanathorn’s leadership, the company’s revenue grew from 16 billion baht in 2001 to 80 billion baht in 2017. Thanathorn oversaw the transformation of the company into a global conglomerate with manufacturing facilities in 7 countries and more than 16,000 employees worldwide.
In 2005, Thanathorn struck a deal with the American auto-maker, Tesla to supply 500,000 cars per year. The deal was noted as a ‘new record’ for Thai Summit Group with total sales of 7.9 billion baht and a profit of 5.98 billion baht.  Thanks to the deal, the Thai Summit Group set up production factories in the United States. In 2009, Thanathorn led the company to acquire the world’s largest mould maker, the Japanese company Ogihara.
Thanathorn served as the President of the Federation of Thai Industrie’s Nakhon Nayok Chapter for two consecutive terms, between 2008 and 2012. He was also the youngest elected Secretary-General of the Thai Auto Parts Manufacturers Association, serving between 2007 and 2010. Thanathorn was also a member of the Industrial Cluster Development Board of Thailand’s National Science and Technology Development Agency.
In May 2018, after 17 years as Executive Vice-President of the Thai Summit Group, Thanathorn resigned from this position after being elected leader of the Future Forward Party.
On 15 March 2018, Thanatorn and Piyabutr Saengkanokkul, a former constitutional law professor at Thammasat University, filed for the creation of a new political party, Future Forward (Thai: อนาคตใหม่), with the Election Commission of Thailand. Thanathorn was unanimously elected as the party’s leader at the party’s first public meeting in May 2018.
Since founding the party, Thanathorn has advocated his political vision for the party; the return of civilian government and demilitarization of Thai politics, greater political accountability, a fairer distribution of wealth, social welfare system to promote human dignity and greater decentralisation of power.
In order to guarantee Future Forward’s independence and transparency, the party has developed a unique funding structure, which relies entirely on donations from party members and supporters. Future Forward Party goal is to raise 350 million baht funds from party members and the public to pursue its campaign in the next 2019 election.
Due to his business experience, young age and political views, international media have drawn a comparisons between Thanathorn and French president Emmanuel Macron and Canadian Prime Minister Justin Trudeau. 
He is occasionally referred by Thai media as the “Billionaire Commoner” which represents the struggle of social class system in Thailand.
Thanathorn and two other senior party members, Jaruwan Sarankate and Klaikong Vaidhyakarn, were charged by police with the Computer Crime Act after an NCPO member filed an allegation against them for transmiting false information or information that damages the country’s stability in relation with the Facebook Live Broadcast on 29th June 2018. 
The three politicians were ordered to meet investigators at the Technology Crime Suppression Division (TCSD) on Friday, 24th August 2018 to hear charges against them. Through their lawyer, they asked to postpone the date to 17th September 2018, saying the order had come at a short notice and they were already tied up with their planned schedule.Thanathorn previously appeared on 31st July 2018 as a witness, but refrain his rights to give any statement on the allegation to the officials.
Thanathorn is married to Rawiphan Juangroongruangkit. They have four children together.
During his spare time, Thanathorn enjoys outdoor activities such as hiking, trekking, climbing, marathons, kayaking, biking, diving and mountaineering. He has participated in various extreme sports competitions, including the Tor Des Géants and the Sahara Marathon. Thanathorn was notably the first Asian to complete the 560KM self-supported foot race above the Arctic Circle.
Asked about his media diet, Thanathorn says he reads foreign newspapers like The New York Times, The Economist, Financial Times, and Thai newspapers like Matichon and Krungthep Turakij (Bangkok Business). He is a big fan of esports and gaming such as Minecraft and Arena of Valor.
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