On hearing of his victory he said he would "firmly deal with" threats from North Korea.
The public broadcaster NHK put Mr Abe's Liberal Democratic Party-led (LDP) coalition at 312 seats, allowing it to retain its two-thirds "super majority".
This is vital to his ambition to revise Japan's post-war pacifist constitution.
Article 9 of the constitution, enacted by the country's American occupiers in 1947, calls for the complete renunciation of war.