In its judgment, the court in the Belgian capital said “there can be no doubt” about jihadist Salah Abdeslam and his co-defendant Sofiane Ayari's involvement in extremism.
Prosecutors had asked for 20-year jail terms for both.
Neither 28-year-old Abdeslam — who is being held in jail in France pending a separate trial over the 2015 Paris attacks in which 130 people died — nor Ayari, 24, were in court for the verdict.
Four police officers were wounded in the gun battle after police acting on a tip-off over the Paris attacks raided a flat in the Forest area of Brussels on March 15, 2016.
Sven Mary, the Belgian lawyer representing Paris attacks suspect Salah Abdeslam. Photo: AFP
Abdeslam, a Belgian-born French national, was arrested three days later in the largely immigrant Molenbeek area of the Belgian capital, near his family home.
On March 22 suicide bombers from a cell linked to the Paris attacks killed 32 people and wounded hundreds more at Brussels airport and a metro station in the Belgian capital.
The judgment said Abdeslam had written a document addressed to his mother saying that “Allah guided me and chose me among his servants to open his path.
It is for that reason that I had to fight the enemies of Allah with all my strength.”
He added that his brother Brahim, who blew himself up during the Paris attacks, “did not commit suicide — he is a hero of Islam.”
The judgment on Monday said that 34 shots in total were fired during the shootout.
Belgian police mounted tight security around the imposing Palace of Justice building in Brussels for the verdict.
'Trust in Allah'
Abdeslam has spent most of the last two years in jail in France.
He was transported to the court from France for the first day of the trial amid tight security including a helicopter escort, while Tunisian national Ayari, 24, is in jail in Belgium.
On the first day of the trial, Abdeslam proclaimed that he would only put his “trust in Allah” and accused the court of being biased against Muslims.
He then refused to attend the rest of the proceedings.
Investigators say Abdeslam's arrest spurred the Brussels bombers to bring forward the 2016 attacks, which had originally been planned for a later date, as they feared they could be captured.
Prosecutors have said that DNA links Abdeslam to the apartment in the Forest district of Brussels where the shooting took place, but not to the weapons that were used.
After Abdeslam refused to return to court for the trial in February, his lawyer Sven Mary sought the case's dismissal on a technicality over how the judges were named to investigate the gun battle, and said media leaks had denied him a fair trial.
But lawyers for police wounded in the gun battle accused Abdeslam of “mocking” the trial.
One of the injured police officers was still suffering from after-effects including brain lesions, epileptic fits and vision and balance problems.
An organisation representing victims of the Brussels attacks and their families has asked for symbolic damages of one euro from the trial.
The Belgian trial is a prelude to a bigger one that Abdeslam will face in France at a later date over the Paris attacks of November 13, 2015, which were claimed by the Islamic State jihadist group.