The Clarets suffered back-to-back defeats for only the second time this season as an early goal from Romal Palmer was enough to give the Tykes victory.
Palmer headed improving Barnsley to their sixth win of the season and pulled them further clear of bottom club Hull City as Burnley drew a blank in front for the second game in a row.
But whereas they were unfortunate to finish pointless in Monday’s defeat to Sheffield Wednesday by the same scoreline, the Clarets could have no complaints at leaving the Oakwell Training Ground empty-handed.
Victory would have taken Steve Stone’s side back level with Birmingham City and Leeds United at the top of the Professional Development League’s northern group.