Johannes Jacobus Steyn, dubbed the "Sunday Rapist", has been sentenced to five life prison terms and 175 years on charges including murder.
On Tuesday, he was found guilty on 33 charges in the high court sitting in Alberton.
Judge Sita Kolbe found him guilty on all but four of the 37 charges brought against him.
Two of those were changed from rape to sexual assault and one was changed from murder to culpable homicide.
The abductions took place between 2008 and 2011 and the girls were aged between 11 and 18.
Among them was 16-year-old Louise de Waal.
The commission for gender equality on Wednesday welcomed the sentencing.
"This will send a strong message that the Sexual Offences Act and other related matters are being taken seriously by the criminal justice system.
"We are concerned by the mitigating factors presented by Mr Steyn's counsel, who seeks to paint the perpetrator as not a violent person, whereas there is compelling evidence to suggest otherwise," said the commission.
The commission thanked all those who testified against Steyn.
"The commission calls on South African men to distance themselves from this behaviour of Mr Steyn of abduction, rape, murder, sexual assault, pointing a firearm, assault and culpable homicide against minors and girls." – Sapa. .