In August 2008, Zheng competed for China in both singles and doubles at the Beijing Olympics. In the singles portion, Zheng made it to the third round before losing to sixth-seeded Dinara Safina of Russia, who eventually won the singles silver medal. Zheng had better results in doubles with her partner Yan Zi, where they were seeded eighth. After losing in the semifinals to the fourth-seeded Spanish team of Anabel Medina Garrigues and Virginia Ruano Pascual for a spot in the gold medal final, they won the bronze medal match against the Ukrainian sisters team of Alona and Kateryna Bondarenko. This was the second Olympics tennis medal ever won by China.