The maker of the black taxi cab, Manganese Bronze, says it is to move manufacturing of its TX4 vehicles' body panels and chassis to China.
The move will cost 60 jobs in Coventry in the West Midlands, the firm says.
It says the parts for the TX4 vehicles will be made in Shanghai, after a UK supplier's decision to cease production of a specialist painting process.
But it says 60% of its cabs' components will still be UK-made, and the TX4 will still be assembled in Coventry.
Manganese Bronze also announced an underlying pre-tax losses of £8.1m for 2009 compared with a loss of £6.2m in 2008.
UK vehicle sales fell from 1,951 to 1,724 in 2009, and the firm said the UK market continued to be challenging.