The NASA Distinguished Service Medal is the second highest award which may be bestowed by the National Aeronautics and Space Administration, ranking immediately below the Congressional Space Medal of Honor. The medal may be presented to any member of the Federal government, including both military astronauts and civilian employees.

The NASA Distinguished Service Medal is awarded to those who display distinguished service, ability, or courage, and have personally made a contribution representing substantial progress to the NASA mission. The contribution must be so extraordinary that other forms of recognition would be inadequate.

Typical presentations of the NASA Distinguished Service Medal included awards to senior NASA administrators, mission control leaders, and astronauts who have completed numerous successful spaceflights. Due to the prestige of the award, the decoration is authorized for wear on active uniforms of the United States military. Another such authorized decoration is the NASA Space Flight Medal.