Alotau 's centre Sohanna Giton was instrumental in the win, directing the flow of traffic down to her shooters to score.
Goal attack Veila Tom scored the bulk of the goals for her team in the first half as Alotau took a 22-5 lead going into the break.
The second half saw some fight from Motu Koita which saw them reach double figures. But Alotau continued to dominate possession and keep the scoreboard ticking.
Alotau coach Sammar Marc said he was very proud of the team which had caused upsets over Kairuku Hiri (1) and (2), Motu Koita West (1), Motu Koita South and Central Province.
"We're a small centre but our girls are showing other centres that we can play netball too," said Marc.