The online activities will be handled by Media Contacts, the interactive arm of Havas Media.
Hermès will be handled by the Havas Media Greater China network in Shanghai, Hong Kong and Taipei.
China's luxury sector is booming at the moment. Last year the market made up only 2.7 per cent of global sales, according to Bain & Co, but is expected to grow rapidly as mature markets such as Japan plateau or decline.