The Cherries took command with two goals in three minutes in the first half, sandwiching a penalty miss by the home side.
Leading marksman Lewis Grabban opened the scoring in the 27th minute, squeezing an angled shot through the legs of Steve Mildenhall.
A minute later Scunthorpe squandered a great chance to get back on level terms when veteran former England keeper David James blocked away a poorly struck penalty from Mike Grella after handball by defender Steven Cook.
Sixty seconds later Bournemouth made it 2-0 in bizarre fashion when a clearance inside the box struck Wes Fogden and looped back into the net over Mildenhall.
Struggling Scunthorpe, badly hit by injury and suspension, were forced to drag teenage striker Jamie Wootton out of a morning youth-team match at half-time to figure on the substitutes' bench for the first time, and he was handed his debut in the closing 10 minutes.
Scunthorpe were awarded another penalty when Shaun MacDonald handled and Karl Hawley drilled it confidently past James in the 63rd minute - but it could not save his side from a seventh home defeat of the season.