Piszczek made his debut for the Poland national team in a friendly match against Estonia on 3 February 2007.

On 6 June 2008, he was selected for the final 23-man squad for UEFA Euro 2008, replacing Jakub Błaszczykowski, who was left out through injury.
He made one appearance at the tournament, coming on a substitute against Germany, but after receiving a training injury, did not play in the next match and had no further role in the tournament.

On 29 July 2011, the Polish Football Association gave a six-month suspension on Piszczek for participation in the fixing of a 2006 match against KS Cracovia match, in which he did not play.
In September 2011, the suspension was cancelled.

Piszczek was selected for the final 23-man squad for UEFA Euro 2012.
He played in all three group games for Poland.
On 22 March 2013, Piszczek scored his first goal for the national team in a 1–3 defeat to Ukraine.
Four days later, he scored in a 5–0 win over San Marino.

He was also selected for the final 23-man squad for UEFA Euro 2016.
Piszczek made his 50th appearance for the national team in the quarter-final match against Portugal, which Poland lost.
Piszczek was selected for the final 23-man squad for the 2018 FIFA World Cup.
However, following a disappointing tournament performance with Poland, Piszczek confirmed his retirement from international football.

On November 2019, he was named to the national team for Euro 2020 qualifying matches with Israel and Slovenia.
He started the Slovenia match in what was dubbed his farewell game, and received a standing ovation from supporters and a guard of honour from his fellow players when he was subbed off just before half time.
Poland went on to win the match 3-2.
Piszczek made his debut for the Poland national team in a friendly match against Estonia on 3 February 2007.
On 6 June 2008, he was selected for the final 23-man squad for UEFA Euro 2008, replacing Jakub Błaszczykowski, who was left out through injury. He made one appearance at the tournament, coming on a substitute against Germany, but after receiving a training injury, did not play in the next match and had no further role in the tournament.
On 29 July 2011, the Polish Football Association gave a six-month suspension on Piszczek for participation in the fixing of a 2006 match against KS Cracovia match, in which he did not play. In September 2011, the suspension was cancelled.
Piszczek was selected for the final 23-man squad for UEFA Euro 2012. He played in all three group games for Poland. On 22 March 2013, Piszczek scored his first goal for the national team in a 1–3 defeat to Ukraine. Four days later, he scored in a 5–0 win over San Marino.
He was also selected for the final 23-man squad for UEFA Euro 2016. Piszczek made his 50th appearance for the national team in the quarter-final match against Portugal, which Poland lost. Piszczek was selected for the final 23-man squad for the 2018 FIFA World Cup. However, following a disappointing tournament performance with Poland, Piszczek confirmed his retirement from international football.
On November 2019, he was named to the national team for Euro 2020 qualifying matches with Israel and Slovenia. He started the Slovenia match in what was dubbed his farewell game, and received a standing ovation from supporters and a guard of honour from his fellow players when he was subbed off just before half time. Poland went on to win the match 3-2.
Łukasz Piszczek