A Perth man who is already accused of sexually abusing and indecently recording three young girls has been charged with further offences, including the possession of about 2 million images and recordings of child exploitation.

The man, 43, was first charged in April after an investigation by the Child Abuse Squad, which included a search of his Marangaroo home.

Police said they seized 19 computers and electronic storage devices, with some allegedly containing child exploitation material that featured three young girls.

A further analysis of the electronic devices was undertaken and it is alleged that out of the 12 million electronic images and recordings viewed by officers, about 2 million were child exploitation material.

Police alleged they identified a further six victims from the material - all girls aged between five and nine.

The man is facing almost 80 charges including indecent dealing with a child, having a sexual relationship with a child, sexual penetration of a child under 13, possessing child exploitation material and distributing child exploitation material.

He is due to appear in the Perth Magistrates Court next month.