Hamline lost by set scores of 26-24, 25-15, 25-10.
The opening set played even, as the two teams tied the score 13 times.
All four timeouts of the set were used by the coaches nine points of the set as each team tried to bounce back from a point deficit to open strong.
Ultimately, a Piper attacking error gave Bethel the opening set.
The Royals took control early in each of the next two sets, ensuring the three-set win over the visitors.
Hamline was led by 10 kills from Sam Greeney-Hamline (Fy., Rochester, Minn.) and 30 digs from Heidi Larsen (Sr., Andover, Minn.).
Larsen will graduate as the school's all-time digs leader with 2,036 career digs.
The Pipers end the season with a record of 10-18, 2-9 MIAC. The Royals are 13-16, 5-6 MIAC.