Poland is not planning to reinstate the death penalty, European Commission President Jose Manuel Barroso has said.
Mr Kaczynski believes Poland has an issue with its image
Mr Barroso said he was reassured on the issue by new Polish PM Jaroslaw Kaczynski during talks in Brussels.
Mr Kaczynski's recent suggestion about the need to start a debate on the issue caused concern in Brussels. The death penalty is outlawed in the EU.
Mr Kaczynski's visit to Brussels is aimed at improving Poland's negative image, Polish officials say.
Poland's new government has also been criticised on its stance on gay rights and its populist economic policies.
Mr Kaczynski's conservative Law and Justice party came to power last autumn.
Since then, the EU's biggest newcomer has been accused of economic nationalism and failing to engage in the debate shaping the 25-member bloc's future.
Mr Kaczynski's coalition also includes populist and right-wing Catholic parties whose views are considered out of step with the mainstream in Western Europe, BBC's Adam Easton reports.
The European Commission earlier this year condemned the governing party's proposal to debate bringing back the death penalty.
In response, Mr Kaczynski said the government had no plans to reintroduce capital punishment.
In June, the European Parliament passed a resolution criticising Poland for rising intolerance towards gay and Jewish people.
At home, the prime minister has a reputation for having an uncompromising domestic vision but little interest in foreign affairs.