The motoring business, which employs about 500 people from around the borough, will add a four storey office block and vehicle workshop to the Watling Street site (A5).
Up to 70 new jobs will be introduced within the company next year, with 30 full-time and 20 part-time positions being created by the expansion.
Work will start on the control tower in March and everying should be finished by January 2012.
Terry Spall, commercial director of MIRA Technology Park, said: "We have got the big development going on and this is sort of attached to it, so we're very pleased that it has gone through because obviously it gets us off to a good start.
"Having these new facilities gives us more space and allows us to have more companies that want to be at MIRA here.
"At the minute our testers are still in the Second World War building and that's the first thing people see when they visit the company, so the new control tower will give people the right image.
"We're working very closely with the borough council and consulting with the local community so we're hoping that we can continue to progress as a company."
Storage units already on site will be demolished to make way for the workshop, which will be made up of six warehouse units containing an office, workshop, shower and a kitchen on the ground level, with a mezzanine floor creating storage and an office space above.
The office block will include meeting and conference rooms, proving ground control rooms and a terrace as well as offices.
The decision was made at a meeting of Hinckley and Bosworth Borough's planning committee on Wednesday, January 5th.