In Germany, Belgium and Luxembourg, support remains relatively high, with more than 50 percent of respondents approving EU leadership, Gallup said. Germany is currently the strongest country in the EU, while Belgium and Luxembourg are home to many EU institutions.
Support dropped precipitously in Cyprus, Greece and Spain, all countries that have had to adopt austerity measures in return for EU bailouts. In Spain, where 59 percent of respondents in 2008 backed the EU, support was down to 27 percent in 2013.
In Greece and Cyprus, support dropped from 32 percent and 39 percent in 2010 to 19 percent and 21 percent in 2013.
Generally, young people between the ages of 15 and 24 have been most supportive of the EU. But Gallup said high unemployment among the young in some European countries has made them less enthusiastic.
In most countries, Gallup has interviewed about 1,000 adults age 15 and older every year. The sample was 500 in Cyprus, excluding the Turkish-controlled part of the country, and 750 in Germany.
The margins of error ranges between 3.5 and 5.3 percentage points for entire-country samples.