Former Arsenal and France striker Henry put New York ahead in the fourth minute with a smart close-range finish after good work from Jamaican Dane Richards.
The Galaxy fought back well though and Donovan, after missing a good chance, floated in a great cross for Colombian forward Juan Pablo Angel, who headed home but had his effort ruled out for offside.
Donovan, the U.S international, brought L.A level four minutes before the break when the influential ex-England midfielder David Beckham curled in a corner from the left and Donovan rose, unmarked, to powerfully head in.
The pair combined again when Beckham, who had a strong game in central midfield, drifted a ball over the top and Donovan rounded Red Bulls keeper Bouna Coundoul, but shot weakly into an open goal and Tim Ream slid in to clear well off the line.
After an entertaining and high-quality first half, the action died off a little in the second 45 minutes but Beckham forced a fine save out of Coundoul with a trademark, bending 25 yard free-kick while at the other end Richards struck the post with nine minutes remaining.
The Red Bulls remain top of the Eastern Conference on 15 points while the Galaxy head the West.
Real Salt Lake beat Chivas USA 1-0 but paid a heavy price with Argentine playmaker Javier Morales suffering a broken ankle which is likely to keep him out for a large part of the season.
