Jason Puncheon's 16th-minute strike secured back-to-back wins for Palace and moved them level on points with the Tigers, who have now lost four on the trot.
But Bruce felt his side were denied two clear penalties by referee Roger East, who then infuriated the City boss further by sending off his goalkeeper Allan McGregor in stoppage time.
"I think we have a blatant call for two penalties, for me the referee has got them wrong," he said.
"I can't say too much as I had a 10 grand fine six weeks ago, but the one where their full-back clatters Nikica Jelavic was bad ebough. Then the one on Shane Long by Danny Gabbidon - it's beyond me that the ref doesn't give it."
Bruce certainly had a point about the second penalty shout after Long, making his Hull debut, was sent sprawling by Gabbidon's clumsy challenge.
But referee East saw nothing untoward and Bruce's mood worsened moments later when Puncheon, whose goal last weekend sank Stoke, struck what proved to be the winner.
There was more than an element of fortune about the goal as well.
Yannick Bolasie reached the byline and his cross - at the second attempt - reached Puncheon, whose initial header was flying well wide.
However, it hit the back of team-mate Marouane Chamakh and fell perfectly for Puncheon to crash high into the net.
Hull attempted to hit back after the break but Jake Livermore blazed a good chance over and Liam Rosenior prodded wide from all of two yards.
And Bruce's misery was compounded when McGregor reacted angrily to a late challenge from Stuart O'Keefe and was shown a red card.
"(The ref) told me he's kicked him, but the challenge on him is horrific," said Bruce.
"McGregor tried to restrain himself - he's thought abut kicking him and had every right to do so - but then restrained himself to make it innocuous."
Eagles boss Tony Pulis will now spend the rest of the week trying to add to his squad, although his current players are doing their best to prove he need not bother.
While Hull paraded a new £14million strikeforce in Long and Jelavic, Pulis has yet to bring in anyone so far this month.
"We are hoping and praying the next couple of days will see us bring a few in," he said.
"We need to. Everyone is working hard behind the scenes. But you can't criticise what players have done, they've been wonderful.
"We need another 17 points. There's 15 games to go and we still need more than a point a game, and in the Premier League that's tough.
"Its a massive ask, so we wont get carried away - we can't afford too. We are pleased with the points we have so far but we can't take our foot off the pedal."