The short clip shared on the social media site shows images of Lawlor, who was killed in broad daylight in in north Belfast in April 2020, followed by a photograph of a coffin.
The clip is titled: 'Robbie the scumbag.'
The TikTok video also displays an image of the tragic teenager, Keane Mulready-Woods, who Lawlor is suspected of killing.
The video, accompanied by a snippet of dance music, then ends with the image of a coffin.
Under the clip, one user has written: "I'd never say this lightly, but Lawlor was pure evil. It's not a bad thing that he's dead."
While another has posted: "Robbie wasn't much of a big man when he went up north."
However, other users have hit out at people mocking the dead, with one person saying: "all those that are saying nasty comments are mental cases."
Mulready-Woods, from Drogheda, was last seen on January 12 before his dismembered body was discovered a week later.
One bag with his limbs was dumped on a pavement in Darndale week later. The next day his head, hands and other body parts were found in a burnt out car in Drumcondra.
Gardai believe that Lawlor was involved in the grim killing.
Lawlor, who is suspected of murdering at least four people, was subsequently assassinated by a lone gunman in Belfast in April of that year.
He was killed in broad daylight outside a house at Etna Drive in the Ardoyne district by a gunman who emerged from the property and opened fire.
The 36-year-old's murder is believed to be connected to a deadly drugs dispute among organised crime gangs with connections to Drogheda, Dublin, Sligo and beyond Ireland.
Four killings and a series of other gun and bomb attacks have been linked to the feud.
Earlier this month Mark Hall was murdered in west Belfast.
His death has been linked to that of his close pal Warren Crossan who was assassinated for his involvement in Lawlor’s killing.
Father-of-one Hall was brutally gunned down on Saturday, December 18, as he sat in the front room of his mum's house in Belfast.
Close sources to the slain man say that while he was making moves to leave his criminal lifestyle behind him, he was consumed with avenging the murder of his childhood friend Crossan who was gunned down in similar circumstances in 2020 just streets away.
They also insisted he was not involved in any way with the murder of Robbie Lawlor, a murder Warren Crossan was linked to and for which he paid the ultimate price.