Opposition factions, including left-wing and Islamist parties, had called for a boycott of Thursday's vote, citing voter intimidation, and accused the authorities of ballot rigging.
The 72-year-old leader, who has suffered severe health problems in recent years, changed the constitution last November to allow himself to run for a third consecutive presidential term, sparking outrage among the opposition.
The president's nearest competitor in the election was Louisa Hanoune, 55, who received only 4.2% of the vote, according to Interior Minister Yazid Zerhouni. The ministry put voter turnout at 74%.
Election observers from the Arab League deemed the vote free and fair. However, no Western observers assessed the election.
Bouteflika, who has ruled the North African country since 1999, has been widely credited with bringing relative stability to a country that had been marred by insurgent violence for decades.