Organiser Clarion Events cancelled the show, which was due to take place at Earls Court in June, after a 12-month consultation period with the automotive industry.
Clarion Show director Carsten Holm says: "The car market in London and the south east is one of the most important in the world and it deserves an event which reflects this.
“While it is possible that we could have staged an event with the current level of support, we are concerned that it would not have met our visitors' expectations.”
He apologised to show supporters and manufacturers who had given up their time to help develop the concept of the show.
The 2001 London Motor Show was also cancelled due to lack of manufacturer support. The latest announcement casts doubt on the long-term future of the show.