After their narrow defeat to Borussia Moenchengladbach in the semi-final stage, Dortmund recorded their fifth win of pre-season with a Jonas Hofmann first-half strike.
Jurgen Klopp's side had to withstand some early Hamburg pressure but remained solid in defence and always looked dangerous going forward.
Hamburg's side contained two ex-Dortmund players, Lasse Sobiech and Kerem Demirbay, while neither Henrikh Mkhitaryan nor Pierre-Emerick Aubameyang were involved for Dortmund.
Marco Reus impressed in attack for BVB and although he was unable to test Sven Neuhaus directly, he turned provider midway through the first half for Hofmann.
The Germany international played a perfect through-ball to find the run of the 21-year-old behind the Hamburg defence, with Hofmann spinning away from Slobodan Rajkovic before curling a shot beyond Neuhaus to give Dortmund the victory.