Neither Abdeslam nor his co-accused, Sofien Ayari, were in court to hear the verdict amid tight security at the Palais de Justice in the Belgian capital.
The two were handed the maximum 20-year sentence, with the court saying their actions had a "terror character".
Abdeslam, 28, is in solitary confinement in a French prison, awaiting another trial for his alleged role in the 2015 Paris Terror Attacks which killed 130 people. It is unclear when that will be.
Prosecutors say he is the lone survivor of an Islamic State death squad. His brother Brahim was one of the suicide bombers.
Monday's verdict followed a shootout with police in the Forest area of Brussels in March 2016, four months after the attacks in the French capital.
Abdeslam was close to being arrested in a Brussels hideout when he and Ayari fled.
Another man sprayed gunfire at police and was killed. Three officers were wounded, one of whom has suffered brain lesions, epileptic fits and problems with balance and vision.
Three days later, Abdeslam was finally caught in the Molenbeek area of the Belgian capital, near his family home.
4 days after that, 32 people were killed in twin terror attacks at Brussels airport and at a metro station.
Investigators suspect that Abdeslam's arrest caused the Brussels attackers to bring their assaults forward amid fears that they too would be captured.
After turning up for the first day of the trial, Abdeslam refused to attend again, claiming the court was biased against Muslims.
Abdeslam told the hearing: I am accused, so I am here. My silence does not make me a criminal or guilty. That is my defence and I am defending myself by remaining silent.