One of four Perth men charged over the "disturbing" and cowardly torture and killing of two kangaroos has pleaded guilty to two animal cruelty offences.

Aveley man Ricky Ian Swan, 28, was charged late last month along with three other men after a police investigation into sickening mobile phone footage of the attacks.

Today, Swan pleaded guilty in the Joondalup Magistrate's Court to inflicting cruelty on a kangaroo and possessing a knife with intent to inflict cruelty on an animal.

The details of the offences were not read in court, and the case was was adjourned until November 28 so that a pre-sentence report could be prepared before Swan is sentenced.

Bullsbrook man Dylan Leslie Griffin, 22, Woodvale man Ben Jaydon Halpuss, 26, and Luke Kevin Dempster, 26, were also charged as part of the police investigation.

Mr Dempster, of Wanneroo, faces an additional charge relating to the alleged torture of an adult chicken by putting it on a fire fuelled by accelerant.

The videos, which were filmed on May 19 and June 16, show the kangaroos being repeatedly stabbed and punched with knuckledusters while their attackers laugh.

One of the animals is seen smouldering from being torched by the men and is shot in the head with a rifle at close range.

The footage shows one of the kangaroos being stabbed more 20 times.

In a final sickening act, the men are filmed spitting on the roos after their deaths.

Detectives investigating the incident described it as one of the most disturbing and horrific instances of animal cruelty they had ever seen.

Swan's three co-accused are yet to plead to their charges.