The Bulls have one of the best records in the NBA, but Derrick Rose will be their only All-Star representative.
Chicago has just three fewer wins than Boston, who had four players selected as Eastern Conference reserves.
"I'm disappointed," Deng said. "To go there and represent the team would've been great. It's weird to me we only have one. All I can do is put it in the past. I really think I'm a step ahead of where I was last year, so my main thing is to keep going forward. There's nothing I can do about it.
"But I'm surprised. As a team, I feel like we went through a lot with injuries. We had Carlos (Boozer) and Joakim (Noah) missing. And I feel like other teams had injuries, and some of those guys that were hurt made it."
Deng then changed his tune, claiming the Bulls are focused on bigger goals.
"We have bigger goals than All-Star," Deng said. "We have a lot of things to prove. I know it's our first year doing so well and being up there with the elite teams. This shows the respect isn't there yet.
"I have no doubt we're going to work hard. And hopefully at the end of the season, we'll get rewarded."