Steven Van de Velde, 21, admitted three counts of rape against a child he met after travelling from Amsterdam in August 2014.
The girl was raped near Furzton Lake and at an address in Milton Keynes.
Van de Velde returned to the Netherlands, but was extradited and arrested in January.
He appeared at Aylesbury Crown Court via a video link for sentencing after admitting all three offences last month.
The court heard he was aware of the girl's age, having had conversations on various social networking sites.
He went to the girl's home when her mother was out and had sex with her, taking her virginity.
Sentencing him, Judge Francis Sheridan said: "You were a potential Olympian. You had the possibility of a stellar future representing the Netherlands.
"She was a child aged 12. You were fully aware of that fact."
Van de Velde - of Cornelis De Wittlaan, Den Haag - travelled from Amsterdam on 2 August 2014, having booked a return ticket with EasyJet that day.
Prosecutor Sandra Beck said: "She had got very close to him via Facebook and spoke regularly. He made her feel very special.
"He is a member of the national volleyball team and she liked what she saw."
Mitigating, Linda Strudwick said: "There is genuine remorse. He has lost a stellar sports career and has been branded a rapist. Plainly it is a career end for him. "
A Dutch international volleyball player who raped a 12-year-old British girl he met on Facebook has been jailed for four years.