Joe Rogan has dragged Donald Trump for his 'not funny' reaction to filmmaker Rob Reiner's gruesome murder. 

The UFC commentator, 58, slammed the president's lengthy Truth Social post that followed the December 14 deaths of Reiner, 78, and his wife, Michele, 70, on the Joe Rogan Experience podcast. 

The couple's death had been ruled homicides - with the victims' son, Nick Reiner, 32, being arrested in connection to the crime - but Trump, 79, declared that Reiner had died from 'Trump derangement syndrome.' 

Rogan said he was less than amused by the president taking Reiner's death as an opportunity to mock the director and producer's vocal left-leaning beliefs.

'The Rob Reiner thing is not funny,' Rogan told his guest, comedian Shane Gillis, 38, during the episode that aired on Christmas Day. 

He said that he saw 'no empathy' coming from Trump during his attack on Reiner.

'I wish he could apologize,' Gillis replied. 'I know he can't and he won't but -'

Rogan continued: 'There's no justification for what he did that makes any sense in a compassionate society.

Joe Rogan addressed the president's reaction to the tragedy on his podcast 

Donald Trump said that Reiner died from 'Trump derangement syndrome' on Truth Social 

Rob Reiner was killed inside his mansion alongside his wife earlier this month 

'It's no different than people celebrating when Charlie Kirk got shot.' 

The podcaster went on to ask Gillis to consider what would have happened if former President Barack Obama had acted in the same brazen manner as Trump. 

'That would be crazy. It just shows you how crazy it is, the way Trump thinks and talks,' Rogan asserted.

'The guy just got sliced up by his kid, you know? Anybody that doesn't see that and go, "F**k, man," you know...' he added before trailing off. 

Reiner and Michele were discovered fatally stabbed in their bed at their stunning mansion in the ritzy Los Angeles neighborhood of Brentwood.