The Paris-based Organization for Economic Cooperation and Development said its latest monthly leading indicator as a whole rose to 100.6 in April from 100.5 in March.
The slight improvement brought the measure, which covers 33 OECD members and is designed to indicate turning points in economic activity, further above the long-term average of 100.
In its twice-yearly Economic Outlook last month, the OECD forecast that the recession-hit euro zone would fall further behind a generally improving United States and a rebounding Japan this year, cutting its global growth estimates.
The monthly leading indicator underlined this, suggesting that the United States and Japan were the only countries among major economies where growth is firming.
The indicator for the United States was unchanged at 101.0 while Japan, whose central bank recently released a wave of massive monetary stimulus on the economy, saw its reading improve to 101.1 from 100.9.
But the euro area did not miss out on the improving outlook with its reading rising to 100.1 from 100.0
The indicator for Germany suggested that growth was returning to trend with a reading of 100.0 for the region's biggest economy after 99.9 in April.
Momentum was stable in France for the third month in a row with a reading of 99.6 while Italy saw a slight improvement to 99.9 from 99.8.
(Reporting by Leigh Thomas Editing by Jeremy Gaunt.)