The result effectively guaranteed safety for the U’s, who have now reached the 50-point mark, while the Minstermen edged six points clear of the bottom two.
Oxford had the best of what few early chances there were with the lively Kemar Roofe causing the visitors problems.
Kyle Vassell fired in a fierce 20-yard shot when the ref allowed advantage after Roofe was brought down, but goalkeeper Michael Ingham was fully behind it.
And at the start of the second half Joe Skarz screwed a shot on the turn wide from seven yards following a free-kick.
York threatened at set pieces and David Winfield saw a far-post header at a corner cleared from just in front of the line by Michael Collins.
Oxford, seeking a third successive win, came to life more when they brought on top scorer Danny Hylton and Patrick Hoban on the hour mark.
And Hoban’s clever chest pass set up Danny Rose for a volley, which he drilled across the face of the goal.
Josh Ruffels tested Ingham with a powerful drive, and later a header, but York held on for a precious point