The Hungary international has switched to the Championship outfit from League One side Portsmouth, as revealed by Sky Sports earlier today.
The 30-year-old Hungary international is the third player to join the Tykes this week following the arrivals of Jonathan Greening and Emile Sinclair on loan from Nottingham Forest and Peterborough, respectively.
Greening's Forest team-mate Marcus Tudgay arrived on loan in time to make his Barnsley debut in last weekend's draw at Bolton.
Buzsaky, who has 20 caps for Hungary, began his career with MTK Hungaria and arrived in England from Porto when he joined Plymouth in 2005.
He signed for QPR for £500,000 in January 2008 following an initial loan spell at Loftus Road and moved on to Portsmouth in October, where he has become a regular since his switch.
Relishing the challenge ahead, he said: "I'm optimistic, I'm ready to fight. I could get into good form at Portsmouth during one and a half months, I could play seven games.
"I got this chance and by this move, I'm one step close to the (Premier League) stage I want to get back to.
"I'll be here on loan until the end of December and Barnsley will have eight games during this period so I'll have time to prove that I can produce well on this stage."