Her reappointment follows Friday's election victory for the Conservative party.
Other ministers who have been confirmed in post include Sajid Javid MP who becomes Secretary of State for Business, Innovation and Skills, John Whittingdale MP who becomes Secretary of State for Culture, Media and Sport, Anna Soubry MP becomes Minister of State (Minister for Small Business) and attends Cabinet and Greg Clark MP becomes Secretary of State for Communities & Local Government.
Commenting on Liz Truss' reappointment, NFU President Meurig Raymond said: "We look forward to working with Liz Truss in her continued capacity as Defra Secretary as we have done for the last 10 months.
"The NFU has been lobbying the next government on key issues in the farming sector and we hope that now we have Ms Truss in place our asks of Government, as well as the Conservative pledges, will be implemented in a timely manner.
"We are eager to work with the Government on their ambitious plan for Britain to grow more, buy more and sell more British food at home and abroad as the NFU and farmers share this ambition. We have already argued strongly that we need such a plan to reverse long-term declines in farming productivity and the nation's self-sufficiency.
"Crucial issues in our sector calling for the Government's immediate attention include problems and issues surrounding BPS. With just weeks to go until the June 15 deadline, it's imperative that enough resource is put in place, as time is running out.
Welcoming Greg Clark as new Communities Secretary, the Town and Country Planning Association's chief executive Kate Henderson said: "There is now a genuine opportunity to focus on the real priorities for the country - housing need, tackling climate change and regional inequalities."
She said the TCPA was also looking forward to working with Clark on "delivering a new generation of garden cities building on the commitment in the Conservative Party election manifesto."