It joins BMW, which announced its decision last year. The company says it has decided to channel resources to other customer events during the year, including equestrian pursuits like the Blenheim horse trials.
'This gets us in front of customers and potential customers,' says a spokesman.
MG Rover and Mitsubishi have, however, confirmed this week, they will be attending the show.
John Sanders, MG Rover sales and marketing director said: 'We have recently achieved spectacular success at other European shows by having a new car on display and Birmingham will be no exception.'
And Jim Tyrrell, Mitsubishi Motors managing director, said: 'Due to the strong demand for our products again this year we have been able to increase our marketing budget. By taking a smaller stand and receiving some financial support from our manufacturer we are delighted to confirm we can now be at the show.'
The SMMT is planning a series of radical changes to the show, at the NEC from October 22 to November 3, as it bids to raise visitor numbers and entice MG Rover and Mitsubishi to exhibit. The two carmakers have yet to decide whether to attend, citing cost as a major sticking point. They are expected to make an announcement by the end of the month.