The poll also found support for the state's landmark 2006 law designed to reduce greenhouse gases has also declined.
The institute says while Californians continue to care about the environment, support for pollution and global warming laws is lower than it was two years ago. The economy and political wrangling in Washington about environmental policy are believed to be responsible for the change.
The change is even more pronounced in the dirtiest areas of Los Angeles County and the Central Valley.
The survey found only 23 percent of Californians consider air pollution a big problem in their area, down 11 points from last year.
The head of the South Coast Air Quality Management District speculates the poll results reflect a lack of public awareness. Barry Wallerstein, executive officer of the AQMD, said the results might be different if Southlanders realized 5,000 Southern California residents die each year due to air pollution.