A second suspect on trial was acquitted of involvement in the shooting, which left two members of the Togolese delegation dead and the team's goalkeeper injured.
"Joao Antonio Puati was sentenced to 24 years," his lawyer Jose Manuel told AFP by telephone, adding that co-accused Daniel Simba had been cleared.
The two men had denied involvement in the shooting, which was claimed by the separatist guerrilla movement, Front for the Liberation of the Enclave of Cabinda (FLEC).
Antonio Nito, attorney general for the disputed oil-rich northern province of Cabinda, where the attack took place, confirmed the verdict.
"Joao Antonio Puati was at the scene and his link with FLEC was established during the trial," Nito told AFP.
"The judge was convinced that Puati took part in the attack," he added.
Wednesday's ruling followed a judgment one week ago that freed four human rights activists jailed almost 12 months ago for crimes against state security, over alleged links to the militant group.
FLEC separatists have been fighting for Cabinda's independence for more than three decades.
Despite a peace deal in 2006, FLEC factions continue to wage low-level attacks in the province, which produces 60 per cent of Angola's oil and is separated from the rest of the country by a strip of territory belonging to the Democratic Republic of the Congo.
A total of nine people were originally arrested in connection with the January attack, but only two of them had any direct link to the shooting, according to Human Rights Watch.
The four activists freed on 22 December -- lawyer Francisco Luemba, university professor Belchior Lanso, Catholic priest Raul Tati and former police officer Jose Benjamin Fuca -- were arrested because they had documents about FLEC and had travelled to Paris for meetings with exiled leaders.
Human Rights Watch (HRW) last week said Angola's government had yet to produce a "credible investigation" into the shooting, and alleged that Puati and Simba had been abused by the military while in custody,