Mnangagwa told his ZANU-PF party supporters at a rally that the 94-year-old Mugabe had been receiving medical care in Singapore for the past two months.
"He (Mugabe) is now old. Of course, he now is unable to walk but whatever he asks for we will provide," Mnangagwa told hundreds of supporters Saturday in Mugabe's home area of Zvimba, about 100 km west of the capital Harare.
"We are looking after him. He is the founding father of the nation of Zimbabwe. He is our founding father of free Zimbabwe.
He said Mugabe was expected back in the country at the end of this month.
"He should have been back on October 25 but his health was not yet good," Mnangagwa said.
"But yesterday we got a message that he thinks he is getting better. He will come back on 30 November."
This month marked a year after Mugabe was toppled in a brief military intervention to end his 37-year grip on power.
Mnangagwa took over from Mugabe and was elected in disputed 30 July elections. He has vowed to revive Zimbabwe's ailing economy by attracting much needed foreign direct investment.