Inflation in the 19 countries sharing the euro currency was 1.2 percent in April compared to last year, for a 0.3 percent monthly rise.
ECB policy makers are debating whether to end a 2.55 trillion euro ($3 trillion) bond-purchasing scheme, which was set up more than three years ago to push inflation back towards a target of close to but below 2 percent.
This target has, however, proved to be an elusive one, as the euro zone economy has showed further signs of slowing growth this year, after steadily emerging from a downturn over the past five years.
Inflation excluding volatile energy and unprocessed food prices, which the ECB uses as its preferred metric of "core" inflation, slowed to 1.1 percent annually in April from 1.3 percent in the previous month.