Yingluck Shinawatra is the youngest of nine children of Loet Shinawatra and Yindi Ramingwong. Her Father was a businessman and member of parliament for Chiang Mai. She is a descendant of a former monarch of Chiang Mai through her maternal grandmother, Princess Chanthip na Chiangmai (Great-great-granddaughter of King Thammalangka of Chiang Mai). Yingluck grew up in Chiang Mai and attended Regina Coeli College, a private girls' school, for the lower secondary level, followed by Yupparaj College, a co-educational school, at the upper secondary level. She graduated with a BA degree from the Faculty of Political Science and Public Administration, at Chiang Mai University in 1988 and received a MPA degree (specialisation in Management Information Systems) from Kentucky State University in 1991.

Yingluck began her career as a sales and marketing intern in 1993 at Shinawatra Directories Co., Ltd., a telephone directory Business founded by AT&T International. She later became the Director of procurement and the Director of operations. In 1994, she became the general manager of Rainbow Media, a subsidiary of International Broadcasting Corporation (which later became TrueVisions). She left as Deputy CEO of IBC in 2002, and became the CEO of Advanced Info Service (AIS), Thailand's largest mobile phone operator. After the sale of Shin Corporation (the parent company of AIS) to Temasek Holdings, Yingluck resigned from AIS, but remained Managing Director of SC Asset Co Ltd, the Shinawatra family property development company. She was investigated by Thailand's Securities and Exchange Commission regarding possible insider trading after she sold shares of her AIS stock for a profit prior to the sale of the Shin Corporation to Temasek Holdings. However, no charges were filed. Yingluck Shinawatra is also a committee member and secretary of the Thaicom Foundation.

Yingluck received 0.68 percent of Shin Corp shares out of the 46.87 percent that Thaksin Shinawatra and his then-wife held in 1999. The military junta-appointed Assets Examination Committee charged that Yingluck made up false transactions and that "there were no real payments for each Ample Rich Co., Ltd shares sold" and “the transactions were made at a cost basis of par value in order to avoid income taxes, and all the dividends paid out by Shin to those people were transferred to [her sister-in-law] Potjaman's bank accounts". However, the AEC did not pursue a case against her. Yingluck, in response, claimed that "her family has been a victim of political persecution".

Born in Chiang Mai Province into a wealthy family of Hakka Chinese descent, Yingluck Shinawatra earned a bachelor's degree from Chiang Mai University and a master's degree from Kentucky State University, both in public administration. She then became an executive in the businesses founded by her elder brother, Thaksin Shinawatra, and later became the President of property developer SC Asset and managing Director of Advanced Info Service. Thaksin served as Prime Minister from 2001 until 2006 when he was overthrown by a military coup. He fled abroad shortly before he was convicted in absentia of using his position to increase his own wealth. He has since lived in self-imposed exile to avoid his sentence in prison.

Exit polls indicated a landslide victory, with Pheu Thai projected to win as many as 310 seats in the 500-seat parliament. However, the official result was 265 seats and 47 percent of the vote for Pheu Thai, with a 75.03 percent election turnout rate. There were 3 million invalid ballots; the large number was cited as the cause for the difference between the exit poll results and the official count. It was only the 2nd time in Thai history that a single party won more than half of the seats in parliament; the first time was in 2005 with Thaksin's own Thai Rak Thai Party.

Yingluck also proposed a general amnesty for all major politically motivated incidents that had taken place since the 2006 coup, which could include the coup itself, court rulings banning Thai Rak Thai and People's Power Party Leaders from seeking office, the People's Alliance for Democracy (PAD) seizures of Government House and Don Muang and Suvarnabhumi Airports, the military crackdowns of 2009 and 2010, and the conviction of Thaksin Shinawatra for abuse of power. The proposal was fiercely attacked by the government, who claimed that it would specifically give amnesty to Thaksin, and also result in the return to him of the 46 billion baht of his wealth that the government had seized as a penalty. However, Yingluck denied that the return of seized assets was a priority for the Pheu Thai party, and repeated that she had no intention of giving amnesty to any one person. Abhisit claimed outright that Yingluck was lying and that amnesty to Thaksin actually was the Pheu Thai party's policy. The government blamed Pheu Thai for the bloodshed during the military crackdown.

Based on the 2007 Thai constitution, public officials can be charged and imprisoned for abuse of power and negligence, even without proof of corruption.

Pheu Thai campaigned with a slogan of "Thaksin thinks, Pheu Thai acts". Yingluck's main campaign theme was reconciliation following the extended political crisis from 2008 to 2010, culminating in the military crackdown on protesters which left nearly 100 protesters dead and thousands injured. She promised to empower the Independent Truth and Reconciliation Commission of Thailand (ITRC), the panel that the Democrat-led government had set up to investigate the killings. The ITRC had complained that its work was hampered by the military and the government.

Yingluck's bank account was among 86 accounts that the Abhisit government accused of being used to Finance the Red Shirt protesters during their demonstrations in 2010. Abhisit accused the Red Shirts of trying to overthrow the monarchy, something they denied. However, the government did not pursue any legal action against her. The Department for Special Investigation found that from 28 April 2009 to May 2010, 150 million baht was deposited into one of her accounts while 166 million baht was withdrawn. On 28 April 2010 alone, 144 million baht was withdrawn.

The 2011 rainy season saw the highest levels of rainfall in Thailand in the previous 50 years. Flooding started in northern Thailand on 31 July, a week prior to Yingluck's appointment as Prime Minister. Flooding quickly spread from the North to the Central Chao Phraya River Basin, and by the beginning of October, the province of Ayutthaya, north of Bangkok, was almost flooded. The floods were the worst in Thailand in over 50 years. Yingluck established centralised flood monitoring and relief operations in mid-August and made tours of flooded provinces beginning 12 August. Yingluck also pledged to invest in long-term flood prevention projects, including the construction of drainage canals. Flood reduction measures were hampered by disputes between people on the different sides of flood barriers: those on the flooded side in some instances sabotaged the barriers, sometimes resulting in armed confrontation. Opposition leader Abhisit Vejjajiva and military Leaders called for Yingluck to declare a state of emergency, claiming that it would give the military greater authority to deal with embankment sabotage. A state of emergency had last been declared in 2010 during the Abhisit-government's crackdown on anti-government protesters. Yingluck refused to declare a state of emergency, saying that it would not improve flood management. Instead, she invoked the 2007 Disaster Prevention and Mitigation Act and issued a disaster warning which gave her government greater authority to manage flood control and drainage.

On 18 January 2012, Yingluck reshuffled her cabinet, assigning six cabinet members to new posts, naming ten new ministers and deputies and dismissing nine members of the government. The regrouping was assessed as a step to increase loyalty to the head of government and a reaction to discontent with the government's management of the flood disaster. Especially noted was the choice of Nalinee Taveesin (Minister in the PM's Office), who is on a US blacklist for alleged Business links to Zimbabwean President Robert Mugabe, and Nattawut Saikua (Deputy Minister of Agriculture), the first leader of the United Front for Democracy Against Dictatorship (UDD, or "Red Shirts") in the government. Yingluck's first cabinet had not incorporated any "Red Shirts" Activists.

Despite being chairperson of the rice committee, Yingluck admitted in the 2013 censure debate against her government that she had never attended meetings of the National Rice Policy Committee.

On 8 May 2014, the National Anti-Corruption Commission (NACC) unanimously agreed to indict Yingluck in the rice-pledging scheme corruption case citing millions of rice farmers who remain unpaid.

On 28 November, Thailand's National Legislative Assembly (NLA) denied the addition of 72 pieces of evidence to her rice-pledging case. The first hearing of her impeachment case was also scheduled to be on 9 January 2015.

On 15 January 2016, the trial against Yingluck began.

On 27 September 2017, in her absence, she was found guilty of dereliction of duty over the rice subsidy scheme and was sentenced to five years in prison.