Treasurer Mr Hockey will go to the backbench, with Social Services Minister Scott Morrison to take over the portfolio, as expected.
Employment Minister Eric Abetz was also relegated to the backbench and his job will be taken over by Michaelia Cash.
Malcolm Turnbull unveils new Cabinet
Joe Hockey loses Treasury, moved to backbench
Mr Hockey intends to resign from Parliament
Scott Morrison named as incoming treasurer
Marise Payne named first female defence minister
She is one of several women being promoted to Cabinet.
Kelly O'Dwyer will be the new assistant treasurer and small business minister.
Mr Turnbull heralded the changes as a "process of renewal".
"As you will have gathered there are some very big changes in the Cabinet, there are now five women in the Cabinet," he said.
"[The] introduction of new talent means that ... others have to leave. One of the great challenges for any leader is to ensure that there is renewal.
"That ... we are able to bring up new talent, new faces, into leadership positions over time, and that often means, that invariably means in fact, that very capable people have to move on stand aside so that others can come through. And that's tough, for everybody concerned. "
Five women now in Cabinet
Foreign Minister Julie Bishop
Health Minister Sussan Ley
Defence Minister Marise Payne (pictured)
Employment Minister, Minister for Women Michaelia Cash
Assistant Treasurer, Small Business Minister Kelly O'Dwyer
Despite the business sector's praise of Bruce Billson's carriage of the small business portfolio, he will now be on the backbench.
Assistant Treasurer Josh Frydenberg will be the new minister for resources, energy and northern Australia, with the former portfolio holder Ian Macfarlane dumped.
Marise Payne will become the nation's first female defence minister, taking over the role from conservative Kevin Andrews.
In another first, Ken Wyatt will become Australia's first Indigenous Government frontbencher taking up the role of assistant health minister.
Key Turnbull-backer Arthur Sinodinos was given the role of cabinet secretary, where he can wield significant influence across the Government.
Another Turnbull lieutenant Scott Ryan will be the assistant Cabinet secretary.
Hockey leaves Treasury, Cabinet, soon to resign from Parliament
Mr Turnbull announced outgoing Treasurer Mr Hockey told him he would not seek a frontbench role.
"The Honourable Joe Hockey told me that he would not be seeking a place in the new ministry and it was his intention to resign from the Parliament in due course," he said.
"Joe has made a long and distinguished contribution to our nation's Government and Parliament over many, many years, for which I thank him."
Mr Hockey released a statement saying: "I advised the Prime Minister that I did not wish to continue as a minister in the Government."
Cabinet reshuffle: Who's going where?
Prime Minister Malcolm Turnbull has named his first ministry. See who is moving where.
"I will have more to say in due course, but for the sake of my young family — to whom I owe so much — I have decided to bring my parliamentary career to a close," he said.
Incoming Treasurer Mr Morrison said he acknowledged the work and dedication of Mr Hockey and "wishes he, Melissa and his family all the very best for their future".
"Joe's leadership of the G20 culminating in his introduction of the multinationals tax package during this past week, his instigation of the asset recycling fund and associated infrastructure works and his treasurership being the turning point in our public finances are a strong and worthy legacy."
Mr Morrison said in the coming weeks he would bring his team together, take briefings and consult widely.
"There is also the need to move forward with MYEFO [Mid-year Economic and Fiscal Outlook] and the Government's response to the various inquiries and projects such as the Tax White Paper that are on foot," he said.
"My intention is to take the same deliberate, conscientious and methodical approach to these issues as I have applied in previous roles."
Pyne moves from education to priority area innovation: Turnbull
Progressive senator Simon Birmingham was given Christopher Pyne's education portfolio, who will remain in Cabinet as Industry Minister.
Mr Pyne's full title will now be minister for industry, innovation and science, a position Mr Turnbull spoke on in his announcement.
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As Prime Minister Malcolm Turnbull announced his new ministry, many of you took to Twitter to express your reactions of shock, surprise, relief and dismay. And then there were the 15 times Mr Turnbull took his glasses on and off...
"Christopher is going to be at the centre as is the whole Government of one of our most important agendas," he said.
"If we want to remain a prosperous, first-world economy [with] generous social welfare safety net, we must be more competitive, we must be more productive, above all we must be more innovative.
"We're not seeking to proof ourselves against the future: we are seeking to embrace it. And this is a Government and a ministry that has that as its focus."
Mitch Fifield's success as a junior minister and key role in helping Mr Turnbull marshal the numbers was rewarded with a promotion to Cabinet as minister for communications and the arts.
Peter Dutton, who prominently supported Mr Abbott in the leadership spill, will remain as Immigration Minister.
Rising star Christian Porter will take over the Social Services portfolio made vacant by Mr Morrison's promotion.
Foreign Minister Julie Bishop, Infrastructure Minister Warren Truss, Environment minister Greg Hunt and Health Minister Sussan Ley are among the senior members of Government who will remain in their current positions.
Ruston's appointment over water a relief for irrigators
Deputy Leader of the Nationals Barnaby Joyce remains Agriculture Minister and gains an assistant minister, Senator Anne Ruston, who will take responsibility for water resources.
The South Australian Liberal Senator lives in the heart of the Riverland and has been a vocal advocate for her state's irrigators.
Senator Ruston's appointment is likely to ease concerns from some South Australian irrigators, who feared their interests would be ignored by Mr Joyce.
Mr Joyce's former parliamentary secretary, Tasmanian Senator Richard Colbeck, has taken on responsibility for tourism and international education, and will assist Andrew Robb on trade.
Mr Robb retains the trade portfolio and responsibility for shepherding the controversial free trade agreement with China through the Parliament.
Meanwhile, Opposition Leader Bill Shorten backed the increased number of women in Cabinet, but said new frontbench faces did not mean changed Government policies.
"We're still seeing the same extreme agenda," Mr Shorten said.
"Malcolm Turnbull has richly rewarded his supporters and punished Mr Abbott's loyalists.
"This is a sign we have more division and dysfunction and Australians don't want to see anymore division and dysfunction in their Government."