The verdict also includes a 10-year disqualification from holding public office, his party, the Pakistan Tehreek-e-Insaf (PTI), said. Bushra Khan, commonly known as Bushra Bibi, was arrested shortly after the verdict, PTI said.
The sentencing by an anti-graft court in Islamabad comes a day after Khan was handed a 10-year jail term in another case in which he was convicted of revealing state secrets, and a week before national elections.
"Another sad day in our judicial system history, which is being dismantled," Khan's media team said, denying the charges.
"No cross questioning allowed, no final argument concluded and decision pops up like a pre-determined process in play," it said, adding "This ridiculous decision will also be challenged."
Khan was also handed a three-year prison sentence in August by another court for selling gifts worth more than 140 million rupees ($501,000) in state possession and received during his 2018-2022 premiership.
Wednesday's verdict was linked to the same matter, but followed an investigation by the country's top anti-graft body, the National Accountability Bureau (NAB), which had also charged his wife in the case.
A prosecution team member, speaking to Reuters on the condition of anonymity, confirmed the verdict. Local broadcaster Geo News reported that the verdict also came with a hefty fine.
Khan's earlier three-year sentence was later suspended but Khan remains behind bars in connection with other cases. He has said that he legally purchased the state gifts.
Government officials have alleged Khan's aides sold the gifts in Dubai.
Khan's earlier conviction resulted in a five-year ban from holding public office, ruling the 71-year-old out of the upcoming Feb 8 election. Wednesday's verdict, however, means that he will be ineligible to hold office till he is 81.
While Khan has been found guilty in two separate cases, this is the first sentencing for his wife Bushra. The two were married in 2018, months before Khan ascended to premiership for the first time. It was Khan's third marriage after two divorces.
