His chief opponent, Ali Benflis, who garnered only 12 % of the vote, said the election on Thursday was marked by "fraud on a massive scale" and vowed not to accept the results.
Election officials said turnout was 51.7% of the North Africa nation's 23 million registered voters, down from the 75% turnout for Bouteflika's last win in 2009.
When asked about the accusations of fraud, Interior Minister Taieb Belaiz detailed the election's lengthy vote-counting procedures.
"Anyone who can overcome all that, I salute their intelligence," he said.
The Algerian commission charged with supervising the election as well and African Union observers said the vote went smoothly.
Bouteflika has officially garnered between 75% and 90% of the vote in Algeria's past four presidential contests - figures described by opposition politicians as inflated. Still he does have a degree of popularity in society.
Aside from being backed by the might of Algeria's powerful state, Bouteflika also represents stability for many Algerians after a decade-long civil war in the 1990s against radical Islamist insurgents.
However, after being hit by a stroke in 2013, Bouteflika was left visibly weakened. The most striking image in Thursday's vote was Bouteflika being wheeled into the polling station to cast his ballot - his first public appearance since May 2012.
The spectre of yet another term for an increasingly frail president did spark a grassroots movement called Barakat ("Enough" in Algerian Arabic) to protest during the campaign.
The demonstrations were swiftly crushed by authorities.