Mr Hunt was previously Culture Secretary, where his behaviour towards Rupert Murdoch's News Corp came under intense scrutiny amid accusations of bias towards News Corp's bid for BSkyB.
Taking charge of the Foreign Office, Hunt said he would be standing "four square" behind the Prime Minister "so that we can get through an agreement with the European Union based on what was agreed by the Cabinet last week at Chequers".
Dominic Raab is the new Brexit Secretary, replacing David Davis who quit on Sunday. In her statement to members of Parliament, May acknowledged the splits in her government and the departures of her ministers.
Jeremy served as attorney general for England and Wales since 2014 but will now turn his attention to media, culture, and all things related to the development of digital radio.
United Kingdom hopes Trump's view of Britain will be positive after visit
This time, his stature on the world stage is bolstered by his unprecedented summit with North Korean leader Kim Jong-un. Trump has dismissed those probes as nothing but a "witch hunt".
Earlier, May defended her Brexit plan to lawmakers in the House of Commons, with Johnson absent from his usual place on the Conservative front bench. Steve Baker, a junior Brexit minister, resigned along with Davis.
Embattled British Prime Minister Theresa May has sought to curb the growing turmoil around her leadership with the appointment of United Kingdom health secretary Jeremy Hunt as the new foreign secretary to replace Boris Johnson. "I am deeply concerned at the position of the British government and urge them to embrace this vital issue".
But it soon began to unravel, when Davis resigned late on Sunday and launched a no-holds-barred attack on her plan, calling it "dangerous" and one which would give "too much away, too easily" to European Union negotiators, who would simply ask for more. Under Conservative Party rules, a leadership race could be triggered if at least 48 of her MPs declared their support for one.
Johnson's resignation was more perilous for May given his seniority in government.
Opposition Labour Party leader Jeremy Corbyn said the government was incapable of delivering Brexit.