Sheffield Wednesday have been the better team but Cardiff City have gone into the half-time break on level terms at Hillsborough.
The hosts made the more enterprising start, as Don Cowie was forced to block an early effort before David Marshall saved well down low.
Malky Mackay's men were sloppy in possession, while the Owls' midfield asserted their authority.
Leroy Lita was asking plenty of questions of the Bluebirds' defence, but he was unable to squeeze his shot past David Nugent.
Dave Jones's men continued to press forward, but fell behind against the run of play as Cowie found the back of the net on the stroke of half time.
