Stephen John Head, formerly of Baird Crescent, Leven, in Scotland, appeared before Sheffield Crown Court
The 56-year-old admitted to 26 charges of sexual offences involving children at an earlier hearing on Monday 2 August.
Head was sentenced to 20 years and 12 weeks in prison as well as being placed on the Sex Offenders Register for life and made the subject of a Sexual Harm Prevention Order.
During the late 1980’s and early 1990’s Head assaulted the three children, who cannot be named for legal reasons, in Doncaster.
Speaking after the sentencing, investigating officer Alexandra Storey, said: “All three of the victims in this case were incredibly brave to come forward and report the horrific abuse they suffered at the hands of Stephen Head. I know that the original Investigating Officer Alison Shields is grateful to all of them for the support they have given during the lengthy investigation.
“We hope that the significant custodial sentence handed down to Head yesterday will provide his victims with some comfort as they continue on their journey of recovery.
“I also hope this result will give other victims of historic sexual abuse the confidence to talk to us.”
If you have concerns, you can call police on 101. You can also call Crimestoppers anonymously on 0800 555 111, the NSPCC helpline on 0808 800 5000, and if you’re under 18 you can contact Childline on 0800 1111. The national helpline Say Something is also available – you can call or text 116 000.