Trailing Republican Rick Scott by one percentage point and about 68,000 votes out of over 5 million cast, Sink said she "just fell a little bit short."
Sink conceded to Scott from her Tampa headquarters around 10:30 a.m., thanking the voters who came out and adding it was "remarkable" how close she came.
"There is no path to victory for us," an emotional Sink said. "Rick Scott will be the next Governor of the state of Florida.
Sink said she called Scott to congratulate him and give him advice.
"I told him that especially after such a close election, he will need to work hard to bring our state together," said Sink. "For the future of our state, I hope Rick Scott remembers there are two and a half million Floridians who did not vote for him and that his highest priority has to be to bring our state together."
Sink seemed choked up as she talked about her campaign and the future of Florida.
"I've seen lots of ups and downs...every morning we will wake up to a new day and to another day and let's think about today as we look out this window," Sink said. "The sun is shining in Florida and my greatest hope is that the sun will continue to shine in Florida."
Just after noon, Scott gave his victory speech, thanking his supporters and the voters.
"Florida is open for business!" an excited Scott told the assembled crowd. "The people of Florida knew exactly what they wanted...they said 'let's get to work.'"
Scott promised to uphold his campaign promise of creating more jobs and urged those who voted for Sink to keep the faith.
"I know I have some work to do to earn your support and I'm going to do my best," said Scott. "Starting today, I work for every Floridian.
"Don't give up, I'm giving you my word, better days are coming."
Scott and Sink had been locked in a dead heat heading into Election Day, with polls showing Sink maintaining the slimmest of leads over Scott. Both candidates voted in their hometowns Tuesday, Scott in Naples and Sink in Thonotosassa, near Tampa.
As the results trickled in late Tuesday and into early Wednesday, Sink refused to concede.
"There are still hundreds of thousands of votes to be counted," Sink told supporters early Wednesday. "We're gonna let the people of Florida, all the people of Florida, have their voices heard."
A short time later, Scott addressed his supporters outside the Hilton Marina in Fort Lauderdale.
"I am absolutely confident I will be the next great governor of the State of Florida," Scott said. "We look forward to finishing the count. We know we're gonna win, we have won and we look forward to getting this state back to work."
The 57-year-old Scott ran as the jobs candidate, promising to create 700,000 jobs in seven years. Other promises include slashing the state budget, drug testing for welfare recipients and smaller government.
A millionaire former hospital CEO, Scott dropped a whopping $73 million of his own cash on his campaign which began in April. With an anti-establishment message and tea party backing, Scott beat Attorney General Bill McCollum for the GOP nomination in the August primary.
In her concession speech, Sink pointed to the money Scott spent as one of two reasons for her defeat.
"We lost because of forces beyond our control," said Sink. "I think between the money and the mood of the country, those were the two forces beyond our control, and so here I am."
Scott joked about the millions spent on the campaign when he mentioned his daughters during his victory speech, saying they might have "lost a little of their inheritance."
A political newcomer, Scott was able to paint Sink as a "Tallahassee insider" who voted along with President Barack Obama.
Sink, 62, worked for 26 years in the banking business, eventually becoming one of the state's most prominent businesswomen. She was elected Florida's CFO in 2006.