In a quarterly poll conducted Nov. 7-11, only 37 percent of respondents indicated the stock market was a good or excellent way to increase wealth.
The largest group, 46 percent of respondents, indicated the stock market was a fair choice for growing wealth, while 16 percent indicated they believed it was a poor choice.
The odds shift when respondents indicate they have $100,000 or more to invest. Fifty percent of respondents with that much available to invest indicated the stock market was an excellent or a good option.
The survey included U.S. adults with $10,000 or more in savings or investments, about 40 percent of the general public, Gallup said.
Opinions also shift when respondents considered only short term investing.
Fifty percent of the respondents indicated they were somewhat or very optimistic about the stock market for the next 12 months, while a smaller group, 39 percent, indicated they were optimistic about economic growth. Even fewer, 36 percent, were optimistic the unemployment rate would drop, while 30 percent indicated optimism about inflation.
Confidence in the stock market appears low when considering how markets have performed this year, Gallup said.
"The stock market is poised to end the year up nearly 25 percent, offering investors impressive gains that should help many recoup the losses they experienced during the 2008-2009 recession," Gallup said.
"Still, U.S. investors' positive outlook seems muted," the firm said.
Results of the survey were derived from a random sample of 1,014 responses to Gallup's daily tracking survey, limited to respondents with $10,000 or more available for investment.
The results have a margin of error of plus and minus three percentage points, it can be said with 95 percent certainty, Gallup said.