Renault Retail Group is reviewing the future of its dealerships in Dartford and London City as part of wider measures to ride out the recession.
Its Beddington Farm bodyshop and service centre in Croydon is also facing closure, and other sites may be restructured.
Managing director Ian Plummer said the group has to streamline its operations "wherever possible", in line with most other businesses in motor retail.
One in four Renault sales
“While everyone is trading under difficult circumstances at the moment, we also have an eye on the long-term and have reluctantly put forward these proposals to safeguard the future of staff at other sites within the group," he added.
Following the closures, Central London will be covered by its dealerships at Acton and Ilford.
Renault Retail Group accounts for approximately one in four Renault vehicles sold in the UK.