Robin Noble was sentenced to eight years’ imprisonment, following a trial at Maidstone Crown Court.
He committed a series of offences with one of the victims between 2008 and 2012, and with a second victim between 2005 and 2013.
The abuse was reported to Kent Police and he was arrested on 13 December 2018.
Noble, of Halstead near Sevenoaks, was later charged with multiple sexual offences involving children and six counts of making indecent images of children.
He pleaded guilty to the indecent image charges but not guilty to the other offences. On 1 April 2022, he was convicted of 16 sexual offences involving children, after a 10-day trial.
Noble, aged 65, was sentenced at Southwark Crown Court on Monday 16 May 2022, when he was also added to the sex offenders register indefinitely and made the subject of a sexual harm prevention order.
Police Investigator, Becki Pike, of the West Kent Child Protection Team, said: ‘Noble subjected his two vulnerable young victims to dreadful crimes for his own gratification and, by pleading not guilty, forced them to revisit their ordeal.
‘The victims displayed tremendous courage in speaking up and then assisting us to bring this appalling man to justice.
‘I would urge anyone who has been a victim of any sexual offence to report this to the police. We have a team of specialist officers who work to ensure that offenders like Noble do not evade justice, just because a crime may have happened a long time ago. We will always treat any information with the upmost confidence and sensitivity.’