Anthony Milford was superb in attack and Sia Soliola dominant in defence as Samoa ran-in five first-half tries to be in a commanding position at half-time.
It took just 80 seconds for the Samoans to open their account as they took advantage of an error-strewn start by PNG. Suaia Matagi reached over and Milford converted.
On nine minutes Antonio Winterstein crossed in the left corner and six minutes later Pita Godinet went over.
Milford showed his skills with a darting run to the posts before PNG winger Josiah Abavu was pulled back for a forward pass.
Winterstein grabbed a second, PNG had a try from Richard Kambo chalked off and then Jason Chan’s kick was taken by Ben Roberts who raced away to score. Milford’s conversion completed the first half scoring.