Reuss, 55, will focus on doubling the resources allocated to electric and autonomous vehicle programs in the next two years, the company said. A mechanical engineer, Reuss' role is expected to be product focused.
His appointment comes as the No.1 U.S. automaker is investing in developing self-driving cars, while cutting back on the production of traditional sedans.
Reuss currently leads GM's global product group and Cadillac operations. He'll keep those roles.
He replaces Dan Ammann, 46, who took over as chief executive of the automaker's majority-owned Cruise self-driving car subsidiary on Jan. 1.
Reuss described the promotion as a "truly great honor," in no small part because his father, Lloyd Reuss, was GM president from 1990 to 1992. The younger Reuss began his GM career in 1983.
GM on Thursday also released its fourth-quarter sales figures.
I'm excited to announce that Mark Reuss, head of our Global Product Group, will take on the role of President @GM. His product knowledge, leadership & passion will drive our transformation as we strengthen our core business & define the future of mobility. https://t.co/Sl0cWcTJ6g— Mary Barra (@mtbarra) January 3, 2019