On 19 May 2010, Piszczek moved to Borussia Dortmund on a free transfer, signing a contract until June 2013. On 26 July 2011, he signed a contract extension to keep him at the club until June 2016. On 24 September 2011, he scored his first goal for his new German club, a last-minute volley to win the match away to Mainz 05 2–1. In the 2012–13 season for Dortmund, Piszczek appeared in 11 out of 12 matches of Dortmund's road to the UEFA Champions League Final in 2013. He also started the final at right-back against Bayern Munich, but Dortmund lost by one goal after Arjen Robben scored an 89th-minute winner for Bayern. On 27 January 2016, Piszczek signed a contract extension to keep him at the club until 2018. On 6 April 2017, he extended his contract with Dortmund until 30 June 2019.