Xiaoyu Guan and Shengying Yan were given first place in the award, which is open to duos representing different countries, all aged under 30.
Teams are given 24 hours to create a PR campaign in response to a client brief, with a panel of judges awarding first, second and third place.
Second place went to Jean Paoli and Raphaële Brachet of Weber Shandwick in France.
The decision not to award Bronze was criticised by Francis Ingham, director general of the PRCA. Ingham, who is also chief executive of ICCO, which is a partner in the Young PR Lions category, tweeted:
PERSONAL VIEW: Huge congrats to China & France for winning Young PR #canneslions Gold & Silver. But decision not to award Bronze simply bizarre & frankly bewildering. If you’re one of 30+ National teams who’ve entered, you’ll feel like this is a slap in the face.— Francis Ingham (@Ingers1975) June 20, 2018
PRWeek contacted Cannes Lions and members of the jury but did not receive a comment at the time of publication.
However, one jury member, Amnesty global creative manager Leila Mountford, tweeted in response to Ingham that the decision "wasn’t taken lightly at all".
Young Lions were also handed out in the Print, Media, Marketer and Design categories, all of which saw Gold, Silver and Bronze awards given.