Two goals by Steve Morison were cancelled out by another double strike by Glenn Murray, denying the home side the opportunity to enter the automatic promotion places.
Afterwards, Holloway was unhappy at what he believed was inconsistency shown by referee Dean Whitestone and felt Leeds should have had two men sent off.
"I felt some of the decisions had a huge bearing on the game - I thought I saw Luke Varney foul Johnnie Williams from behind, a blatant yellow card," he said. "Two minutes later Varney dived and got given a yellow card, and he should have been off.
"Then two minutes later, Wilfried Zaha goes straight through and gets scythed down and (Stephen Warnock) gets a yellow - if that's not a goalscoring opportunity I don't know what the rules are.
"Unfortunately I'm sat here pretty bemused wondering how we were behind in the game. I'm delighted we came back but I was a little bit aggrieved - we missed too many chances."
Leeds manager Neil Warnock was keen to wish his old side well in their promotion push afterward, but was quick to dismiss the complaints by Holloway.
"Palace are a good team, I hope they go up," he said. "But I don't see Holloway complaining with a couple of decisions in the first half.
"They're used to winning here but they didn't deserve to win.
"Varney didn't have to dive, but in the first half he got fouled - but no free-kick. I don't condone that (diving) though."
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- Luke Varney