Paul Griffiths, 49, was sentenced at Leeds Crown Court yesterday after being found guilty of rape and other sexual offences against a girl who is under 10.
Griffiths committed the offences against the girl between 2010 and 2015.
They came to light after the victim told a relative what was happening, who then contacted the police.
Griffiths was later arrested in October 2015 after a police investigation.
DC Victoria Bottomley, who led the investigation, said: “We are pleased Griffiths has received such a substantial sentence for extremely serious crimes committed against a very young and vulnerable child.
“Griffiths targeted and then committed multiple sexual offences against her over a sustained period, behaving in a truly appalling fashion in which he took advantage of a youngster who was in no position to stop him.
“The crimes he committed were as serious as we see here as safeguarding detectives and it is no exaggeration to say he poses a significant danger to children.”
“I wish to commend the courage of the young victim in disclosing these offences, and then telling officers what happened in subsequent police interviews.
“We hope her family, who had their trust abused so badly, can take some comfort in knowing Griffiths will now spend many years behind bars, and monitored as a sex offender.
“I would always urge any victims of sexual offences in Wakefield District to contact the police on 101.
“We will always listen and investigate.”