The National People's Congress ballot unanimously approved Xi for a second term. Wang had a total of 2,969 votes in his favor and only one against.
The election of the two allies as China's top chiefs comes just a week after the Chinese parliament removed term limits on both positions. It also comes on the heels of China planning to formalize rules for its new anti-corruption agency, the National Supervisory Commission, or NSC.
On Saturday morning, the Chinese parliament also approved Xi's plan to reduce the cabinet by 15 positions at ministerial or vice-ministerial levels to make government "better structured," and "more efficient." State Council Wang Yong said the plan would also "strengthen the government's role in economic management," and "environmental protection."
Wang, 69, a close friend of Xi's, had served as head of corruption investigations in China since October, after stepping down from the ruling Communist Party's top echelon, the South China Morning Post reported.
Now, as vice president, Wang is expected to cover global affairs, including addressing China's tumultuous relationship with the United States in light of an expected trade war, the South China Morning Post report stated. Xi is considered the most powerful Chinese leader since Mao Zedong, who chaired the Communist Party until 1976.
"Clearly Xi is shoring up his power, but I would suggest what China also wants to do more than anything else is define a mode of government which is not liberal and at the same time ... is predictable, reliable, which is safe for businesses to invest in," director of the University China Center at Oxford Rana Mitter told CNN.
Meanwhile, Amnesty International and the Brookings Institute have been critical of the new NSC. Amnesty International told CNN it had concerns about the agency's "far-reaching powers." Brookings Institute said citizens would have "little or no legal recourse" to challenge corruption allegations.