The 18-year-old has been part of the Glovers’ matchday squad on six occasions this season but is yet to make an appearance.
Bassett picked up his first Northern Ireland Under-19 caps earlier this month, featuring in two training camp matches against a Wolves Development side and a Stoke City Development side.
The attacker will now link up with former Yeovil fans’ favourite Nick Crittenden, who is assistant player/manager for the Magpies.
After making his debut in September last year, Bassett became the youngest player to represent Yeovil Town in the Football League, taking to the field against Crawley Town aged just 17 years, 6 months and four days old.
Town manager Darren Way believes the loan move is the right one for Bassett to continue his development.
He said: “Dorchester is a good Football Club that we trust and has served us well over the years, plus we know Nick Crittenden and the staff there very well.
“It’s a local move which means we’ll be able to watch his games, plus Ollie will train with us daily so we can still closely monitor his development.”
Everyone at Yeovil Town Football Club wishes Ollie all the best during his time at The Avenue.