Yvette Cooper will be shadow foreign secretary.
Cooper and Balls had been tipped as front runners for the shadow chancellor role, which has been handed to Johnson, a former home secretary.
Meanwhile Andy Burnham will take on the opposition education portfolio, while John Healey will take on health.
John Denham will be pitched against the coalition's Vince Cable as shadow business secretary.
Miliband said his cabinet included a "broad range" of skills.
He added: "My team is united in one central mission for the future – to win back the trust of the British people and take Labour back to power.
"Together, this new generation of Labour will work together to reject the pessimism of this coalition government as we set out our vision of what Britain can achieve.
"Our values are those of the British people, and this shadow cabinet will ensure that the hopes and concerns of working families are at the heart of our offer to the country."
The full list of shadow cabinet positions:
Leader of the Opposition Rt. Hon. Ed Miliband MP
Deputy Leader and Shadow Secretary of State for International Development Rt Hon Harriet Harman MP
Shadow Chancellor of the Exchequer Rt Hon Alan Johnson MP
Shadow Secretary of State for Foreign and Commonwealth Affairs and Minister for Women and Equalities Rt Hon Yvette Cooper MP
Shadow Secretary of State for the Home Department Rt Hon Ed Balls MP
Chief Whip Rt Hon Rosie Winterton MP
Shadow Secretary of State for Education and Election Coordinator Rt Hon Andy Burnham MP
Shadow Lord Chancellor, Secretary of State for Justice (with responsibility for political and constitutional reform) Rt Hon Sadiq Khan MP
Shadow Secretary of State for Work and Pensions Rt Hon Douglas Alexander MP
Shadow Secretary of State for Business, Innovation and Skills Rt Hon John Denham MP
Shadow Secretary of State for Health Rt Hon John Healey MP
Shadow Secretary of State for Communities and Local Government Rt Hon Caroline Flint MP
Shadow Secretary of State for Defence Rt Hon Jim Murphy
Shadow Secretary of State for Energy and Climate Change Meg Hillier MP
Shadow Leader of the House of Commons Rt Hon Hilary Benn MP
Shadow Secretary of State for Transport Maria Eagle MP
Shadow Secretary of State for Environment, Food and Rural Affairs Mary Creagh MP
Shadow Chief Secretary to the Treasury Angela Eagle MP
Shadow Secretary of State for Northern Ireland Rt Hon Shaun Woodward MP
Shadow Secretary of State for Scotland Ann McKechin MP
Shadow Secretary of State for Wales Rt Hon Peter Hain MP
Shadow Secretary of State for Culture, Media and Sport Ivan Lewis MP
Shadow Leader of the House of Lords Baroness Royall of Blaisdon
Shadow Minister for the Olympics Rt Hon Tessa Jowell MP
Shadow Minister for the Cabinet Office Rt Hon Liam Byrne MP
Lords Chief Whip Lord Bassam of Brighton
Shadow Attorney-General Baroness Scotland