Official figures show that euro zone consumer and business confidence fell in June, to the lowest level since October 2009.
This contrasts however, with consumer sentiment across the wider EU which remained stable at 90.4 points.
The European Commission's confidence index for the 17-nation euro zone lost 0.6 points to 89.9 points, marking its third fall in a row.
The euro zone figure was undermined in particular by a 2.2-point decline in a sub-index which measures sentiment in the predominant services sector, while the industrial sector also posted a drop of 1.3 points.
Better results were seen in the retail sector, where the confidence sub-index gained 3.2 points and construction, which was up by 2.1 points.
A breakdown by country showed the strongest declines in France and Germany, the two biggest euro zone economies, while the mood was brighter in Spain and Italy which are both struggling with reforms to correct public finances.
Euro zone private sector activity sank to the lowest level for three years in the second quarter of 2012 as business sentiment deteriorated, a purchasing managers index compiled by business research firm Markit showed last week.
The PMI was stuck at 46 points in June, the same level as May, pointing to another month of contraction in activity.