Is the Surgeon General of the US in the military?

No, but they wear the uniform of a Vice Admiral in the U.S. Navy. In 1987, the Office of the Surgeon General (OSG) was reestablished as a staff office within the Office of the Assistant Secretary for Health. Concomitant with this action, the Surgeon General again became responsible for management of the Commissioned Corps personnel system. (Note: The Surgeon General does not directly supervise all Commissioned Officers; most work in PHS or other agencies and report to line managers of those agencies who may or may not be in the Corps.) In carrying out all responsibilities, the Surgeon General reports to the Assistant Secretary for Health, who is the principal advisor to the Secretary on public health and scientific issues.

As "America's Doctor," they provides the public with scientific information available on how to improve their health and the health of the nation. They also oversee the operational command of 6,500 uniformed health officers who serve in locations around the world to promote, protect, and advance the health of the American People.