China first built the 60,000-seat stadium in 1987, but it has been closed for renovations for the past three years, the official Xinhua news agency said.
"The construction and refurbishment of the stadium cement the traditional friendship between our two countries," it quoted Chinese ambassador to Zimbabwe, Xin Shunkang, as saying.
Zimbabwe's Vice President Joyce Mujuru "thanked China for renovating the stadium and assisting other areas of the Zimbabwean economy", Xinhua added.
The stadium has been "transformed into a world-class stadium that met the standards of the Confederation of African Football", the report said.
China's embassy in Zimbabwe in February threw a birthday party for Mugabe.
Beijing and Chinese companies have pledged tens of billions of dollars to Africa in loans and investments, mostly to secure raw materials for the world's fastest-growing major economy.
Rights groups have repeatedly criticised China for propping up dictatorial and corrupt African nations. China counters it offers no-strings aid and that its pledge not to interfere in any country's internal affairs is welcomed by African nations.
