Kevin Carter, 34, formerly of West Street in Hucknall, appeared at Nottingham Crown Court on 8 April.
He had pleaded not guilty to the offence but was convicted by a jury following trial in February.
It happened in 2018 after the victim woke up to find Carter having sex with her.
Detective Constable Jas Athwal said: "This was a really distressing case which has taken a while to come to court so I'm glad that Carter has been given a strong sentence and that the victim can finally get closure from it all.
"We hope this sends the message out of how completely unacceptable sexual offences are on any level.
"I hope any victims out there know that they can come to us, tell us what they’ve been through so we can do everything we can to investigate and bring such offenders to justice."