The Democratic presidential candidate paid an effective federal tax rate of 34.2 per cent previous year.
Mrs Clinton's running mate Tim Kaine has also released his returns for the past 10 years.
Kaine and his wife, Anne Holton, paid an effective federal tax rate of 20.3 percent in 2015, according to the news release.
The Clintons have disclosed tax returns for every year since 1977, in part due to laws requiring public officials release returns. Their combined payments in federal, state and local taxes amounted to an effective tax rate of 43.2%, the sixth time in 15 years it has exceeded 40%.
Mr Trump says he won't release his return while it is still being audited by the Inland Revenu Service. Trump has said he won't release his until an IRS audit is complete, breaking tradition with every presidential candidate in recent history.
Last July, Clinton posted eight years of her tax returns on her campaign website.
The returns reveal where the Clintons' money came from a year ago, most of which Hillary Clinton spent on the trail after kicking off her campaign in April 2015. In the latest poll released by the Wall Street Journal/NBC News/Marist found #Hillary Clinton stomping Donald Trump in four key, battleground states.
At a Clinton rally last week in Omaha, Nebraska, Buffett, whose Berkshire Hathaway conglomerate is based there, challenged Trump to meet and exchange tax returns. The couple earned more than $10 million in 2015, the documents say.
When asked about his taxes at the time, Nixon willingly released the returns that had been under audit: "I welcome this kind of examination, because people have got to know whether or not their president is a crook".
Donald TrumpDonald TrumpIt might be the end of Trump, but real story of campaign was always Sanders WATCH LIVE: Trump campaigns in Pa.
On August 10 - one day after being savagely attacked for describing Hillary Clinton's plan to "abolish the Second Amendment" - Donald Trump doubled down and pointed out that the media is simply distracting from the fact that the Second Amendment is "under siege".
The video includes 2012 Republican nominee Mitt Romney, Senate Majority Leader Mitch McConnell and Texas Sen.
Read the full article for all the details, and for more on what Clinton has said about gun buybacks, assault weapon bans and the Second Amendment in general. The owners of these so-called "pass-through" corporations report profits of their businesses directly on their personal income-tax returns, much like the rest of us report our wages.
According to public records, Mr Trump did not pay any income taxes in 1978, 1979, and 1984. Her husband made money in a similar fashion: about $29,000 from his books, about $5.25 million from speaking engagements, and more than $1.5 million in consulting fees.