There was little to inspire in the game but Cameron Jerome should have opened the scoring after latching onto a measured Jason Koumas pass.
Nick Montgomery had the Blades' best chances but his first effort was saved and a second cleared the crossbar.
Cardiff boss Dave Jones:
"I've got to be happy coming here and getting a point but we weren't over-run or over-awed, we took it to them and gave them as good as we got.
"We came here set up to win the game, unfortunately for us we only got a point. They were hanging on in the end.
"I don't see the point in going into a game not thinking you can win. If any of my players said 'I don't think we can win this' I'd get rid of them."
Sheff Utd: Kenny, Kozluk (Geary 54), Bromby, Morgan, Unsworth, Gillespie (Ifill 63), Alan Quinn, Jagielka, Montgomery, Kabba, Shipperley (Webber 72).
Subs Not Used: Tonge, Wright.
Cardiff: Alexander, Weston, Loovens, Purse, Barker, Cooper, Whitley, Ledley, Koumas, Jerome, Ricketts (Lee 78).
Subs Not Used: Cox, Ardley, Parry, Margetson.
Ref: C Foy (Merseyside).