It was only the Royals' second home league win of the season and meant they completed a league double over the Yorkshire side.
Reading had the better of the chances in the first half and it was little surprise when they went ahead in the 28th minute.
Andy Griffin sent in a deep cross from the right wing to the far side of the penalty box. Gylfi Sigurdsson was there to turn it back into the middle and Republic of Ireland international Shane Long was able to prod the ball home from close range.
Reading should have had a second midway through the second half but Job McAnuff turned Ryan Bertrand's left-wing cross against the Barnsley woodwork.
Mark Robins has succeeded in turning Barnsley from a relegation threatened team to a mid-table side, but they were always second best in this game.
Reading had come close to taking the lead as early as the fifth minute but Bertrand's corner from the right was headed just wide by Reading skipper Ivar Ingimarsson
Barnsley were playing Jon Macken and Ian Hume up front and Hume was give a stern lecture by referee James Linnington after just seven minutes for his second foul on defender Matt Mills
As Reading continued to create chances, Simon Church shot wide of the upright after being put through by Sigurdsson
McAnuff set up another run by Long but Church could not bring his pass under control and the chance was gone
Adam Hammill gave Reading a fright in the 18th minute with a shot that beat goalkeeper Adam Federici but his effort was blocked near the line byBertrand
Long was presented with a great chance after a mistake by Anderson Silva but, with only the keeper to beat, Long shot straight at him.
Barnsley's chances were few and far between but when they did come both Hume and Macken hit tame efforts wide.
Long and Church were combining well up front for Reading and were certainly more of a threat than Barnsley's throughout the game even though Macken was replaced at half-time by Daniel Bogdanovic.