The company founded in April 2004 said it ceased airing new programs Thursday afternoon and will soon file to be liquidated under Chapter 7 bankruptcy. It began broadcasting reruns of programs and would end those as well Monday night.
Air America said 10 consecutive quarters of declining ad revenue and the difficulty of making money on the Internet contributed to its financial woes.
"The very difficult economic environment has had a significant impact on Air America's business. This past year has seen a `perfect storm' in the media industry generally," the company said in a statement on its Web site.
The network had some 100 radio outlets nationwide.
Franken, a Democrat, hosted his own show from 2004 to 2007 before going on to become a U.S. senator from Minnesota last year after a close election. Maddow went on to host her own TV show on MSNBC.