There were few clear-cut chances until late on in a game riddled with misplaced passes and a lack of quality in the final third.
Jon-Paul Pittman's arrival for the second half briefly sparked Oxford into life, but after producing a sharp turn, Pittman blazed over the bar from a great position.
U's keeper Ryan Clarke parried an effort from Billy Bodin just before the break after the forward cut in from the right, leaving three defenders for dead.
The Gulls threatened at set pieces with Kevin Nicholson's fine delivery and the visitors had a goal disallowed for offside early in the second half.
Torquay keeper Martin Rice, on his Football League debut, made two good saves from Peter Leven, and turned a snapshot from James Constable over the bar. But Constable also blasted over from close in, and in a frantic finale, U's defender Andrew Whing headed against the post at a corner.