Steve Davies's second-half penalty rescued a deserved point for Derby but they missed the chance to go top.
Barnsley goalkeeper Luke Steele produced an excellent display to keep Derby's attacks at bay.
The Tykes led when Jacob Butterfield profited from some poor defending to score from close range 10 minutes before the interval.
Barnsley defender Bobby Hassell brought down Ben Davies on the hour, leading to the penalty that Steve Davies scored.
Nigel Clough's team laid siege to the visitors' goal for the remaining half-hour of the clash but they could not find a winning goal. Steve Davies came closest to netting but his free header in injury time sailed over as Barnsley hung on for their fifth consecutive draw.
Earlier, Steele had tipped wide Jeff Hendrick's 25-yard strike then palmed away a Theo Robinson header. The Barnsley goalkeeper also produced a brilliant point-blank save from Steve Davies.