The plunge marks the highest drop in the rate for Poland since the country entered the European Union in 2004, the Dziennik daily reported, citing Eurostat.
In 2016, 24.2 percent of children in Poland were at risk of poverty or social exclusion. The rate slumped to 17.9 percent last year.
According to Eurostat’s findings so far, Poland’s drop was outpaced only by Romania, where the rate declined 7.5 percentage points to reach 41.7 percent in 2017.
The agency is yet to release data from countries such as Ireland, Croatia, Serbia and Turkey.
Eradicating child poverty is one of the key goals of the Polish government’s flagship "500-plus" child benefit programme.
Poland’s socially conservative Law and Justice government, which came to power in late 2015, aims to ease the burdens of child rearing by giving families with two or more children a handout of PLN 500 (USD 145, EUR 118) a month per child.
Economy expert Jacek Tomkiewicz, from the Leon Koźmiński Academy in Warsaw, said that poverty was waning in Poland due to the improving economic situation in recent years.
He told the rate of children at risk of poverty in Poland stood at 29.8 percent in 2013, giving reason to believe “the major drop in the years 2013-2016 was possible without spectacular social welfare programmes.”
“However, the progress recorded in just one year  is evidently the result of social policies,” he added.