He made the announcement during the country’s Independence Day celebration held in the capital, Harare.
The general election is held every 5 years.
The elections for the president, parliament and local government were held jointly in 2008 and 2013. Some analysts say the 2018 election will also see such multi-election.
Last year, the country’s ruling Zanu-PF party confirmed Mugabe as its sole candidate for the 2018 elections.
Mugabe has governed the Republic of Zimbabwe as the president and prime minister since the country’s independence.