Homegrown defender Matthew Bates scored his second goal of the season with a fine strike from 18 yards in the 71st minute, but Jones headed home late on to make it 1-1.
Boro, who won 3-1 at Deepdale on December 28, are showing signs of improvement under Tony Mowbray and this result extended their unbeaten league run to five matches but Phil Brown's men will heart from their battling display.
Brown, who on Friday apologised for comments he made claiming Middlesbrough's players were unsettled, saw his struggling side make a purposeful start.
Iain Hume crossed dangerously from the flank and Boro defender Seb Hines made a fine clearance to avert the danger. In the 33rd minute, Preston signalled their attacking intent when winger Paul Parry collected possession 20 yards from goal and hit a fierce shot which Boro goalkeeper Jason Steele tipped over the crossbar.
Boro began to increase the pressure and finally struck with 19 minutes remaining when Bates advanced forward from defence and hit a right-foot shot into the bottom left-hand corner from 18 yards. Yet Preston refused to lie down and Jones headed home a cross from Conor McLoughlin with two minutes remaining to salvage a point.