The world's biggest handset maker -- and Finland's largest company by far -- hopes the E7, C7 and C6 will help it regain ground lost to Apple, Android and BlackBerry products.
"Today our fight back to smartphone leadership shifts into high gear," said Niklas Savander, Nokia's Executive VP, Markets.
He said the three new phones, along with the recently-released Nokia N8, form a new, faster-running Symbian product family. He noted that, "despite new competition, Symbian remains the most widely used smartphone platform in the world."
Deliveries are expected to begin before the Christmas shopping season, priced at between 260 and 500 euros.
Savander said Nokia is fighting in earnest to remain number one in the smartphone market. At the moment the company has a market share of around 40 percent.
"In the last quarter, people bought more Nokia smartphones than Apple and Android combined," Savander noted.
"The products are a clear improvement... but we know they are not where Nokia needs to be yet, and any other promise around 'we are working on it' would have not convinced anyone," said Gartner analyst Carolina Milanesi.
"A new CEO and the old guard stepping down might give investors more confidence that things are really changing."
Investors seemed unimpressed by Tuesday's announcements. Nokia's stock price declined by about one percent in afternoon trading.
Neither the company's outgoing CEO Olli-Pekka Kallasvuo nor his replacement Stephen Elop is taking part in the Nokia World gathering.
Anssi Vanjoki, director of Nokia's Mobile Solutions unit, who announced his resignation a day earlier, was welcomed with enthusiastic applause as he appeared on stage.
"We have taken some knocks over the last few years," said Vanjoki, "but we have positioned Nokia for the future."