Gerrans will link up with compatriots Richie Porte, Rohan Dennis and Australian champion Miles Scotson at BMC.
"BMC Racing Team is a team that I have always admired, not only in their results, but also the professionalism of the organization. Obviously, there has always been a strong affiliation with Australians in the team starting with Cadel Evans, and then more recently with Richie Porte, Rohan Dennis and Miles Scotson," Gerrans said.
The 37-year-old hasn't won a race since claiming a fourth Tour Down Under title in 2016 as he turned his attention to playing a road captain role. Gerrans explained that with BMC he is looking forward to new roles and responsiiblities.
"I'm really excited about the position I have been offered in the team. I always saw myself spending the last period of my career in more of a road captain role and passing on my experiences. I'm looking forward to contributing to the team as both a support rider and leader when called upon," he said.
With Gerrans a perennial winner on Australian soil, the January racing calendar with nationals, Tour Down Under, Cadel Evans Great Ocean Road Race and possibly the Herald Sun Tour, are likely to be his first races in the red and black kit as he explained.
"It's probably a bit early to start announcing specific goals but I hope to get my season started in Australia," he said. There is obviously a Santos Tour Down Under crown to defend with Richie Porte, it is a race I've always enjoyed and done well at."
BMC's General Manager Jim Ochowicz explained that he jumped at the opportunity to sign Gerrans and expects the Australian to be a key rider in the 2018 roster.
"There are not many riders out there with a palmarès and wealth of knowledge like Simon Gerrans, so we are very excited to see Simon join us in 2018," Ochowicz said. "Simon's experience in all aspects of the sport and his diverse skill set in multiple race situations will make him a tremendous asset to the team. We expect Simon to play a big role in BMC Racing Team's performance from the beginning of the season until the end."
Ochowicz added that Gerrans will be crucial to the success of its leaders Richie Porte and Greg Van Avermaet throughout the year.
Since turning professional with AG2R Prevoyance, Gerrans' 32 wins include stages of the three Grand Tours, Milano-San Remo, and Liège-Bastogne-Liège.
BMC Racing has also announced the signings of Nathan Van Hooydonck (BMC Development), Alberto Bettiol (Cannondale-Drapac), Jürgen Roelandts (Lotto Soudal) from 2018.