The company, which has an annual production capacity of 150 megawatts of solar panels at its plant in Santa Clara, California raised most of the money from its current investors.
"In this environment I couldn't be happier about it," Chief Executive Officer John Carrington told Reuters.
Solar panel makers have suffered over the past year as the steep 50 percent drop in wholesale prices eroded profit margins, pushing many companies into the red and some smaller players into bankruptcy.
Miasole did not provide details on who provided the new money, but it has previously attracted capital from investors such as Kleiner Perkins Caulfield & Byers, VantagePoint Capital Partners and Firelake Capital Management.
Carrington, who joined the company late last year, said Miasole was still seeking to link up with solar industry players who could help it expand.
"That's a high order of priority and it's something I've been engaged in since joining," he said. "We're talking to a lot of different potential partners and we're confident we can execute on something this year."
Unlike most solar companies that make panels from polysilicon, Miasole uses copper indium gallium selenide, or CIGS, to make solar panels.
CIGS panels have long been seen as a potential challenger to traditional silicon-based panels because they cost less to manufacture, though they typically produce less electricity.
Still, MiaSole has rapidly boosted the power output efficiency from 10.5 percent in January 2011 to 14 percent currently. It expects to reach 15 percent by the end of this year.
In addition, the company expects to get its cost per watt below 80 cents by the end of the year, Carrington said, making it competitive with the world's largest producers.