The Ruhr Valley club take on in-form Stuttgart for a spot in the quarter-finals and apart from Haller, Terzic could also be without Gio Reyna, who is nursing a cold.
"Seb Haller suffered a knee injury in training and will most likely be out for about a week," Terzic told a press conference, adding that Reyna was doubtful after missing training with a cold.
"For Gio it could be tight," he said.
His team drew 1-1 with league leaders Bayer Leverkusen on Sunday and Terzic said his players would now need to improve their performance against Stuttgart if they are to progress in the competition.
"We were not satisfied with the number of attacks we had against Leverkusen. It was something we did far too seldom," Terzic said.
"The goal we scored was a good move but it did not happen often enough."
"We gave the ball away sloppily. It is about doing things we did well more often. That's what we want to do and add to our defensive stability now."
Dortmund lost to third-placed Stuttgart 2-1 in the Bundesliga last month and Terzic said they had drawn their lessons from that defeat.
"We analysed that game from four weeks ago. We will have it in our memory," he said.
"We will learn from that and the things that happened won't happen again. This is a different competition and a knockout match. We want to win and reach the next round."
