Retailers in the 13 countries sharing the euro saw their sales grow more slowly than expected in September despite a solid improvement in Germany.
The volume of retail trade in the euro zone rose 0.3% in September from August and rose 1.6% over 12 months, the European Union's Eurostat data agency said.
The result fell short of economists' expectations for retail sales to rise 0.6% over one month and grow 2.2% over one year.
The disappointing figures came despite solid growth in regional powerhouse Germany, where retail sales rose 2.3% over one month and 1.4% over the year.
September's euro zone sales marked a pick-up after a soft spot in August when retail sales stalled over one month and grew 0.8% over one year, Eurostat said, revising down previous estimates.
Analysts said that euro zone consumers remain relatively cautious in their spending in the face of higher interest rates, heightened concerns over inflation and ongoing worries about long-term personal finances.
Meanwhile, retail sales in the 27-nation EU as a whole rose 0.4% in September over August and increased 3.5% over the year.