This study evaluates to what extent two minority groups, women and homosexuals, in the South Korean defense force have been integrated and what factors have played a critical role in increasing their integration and acceptance in the military. The key question of this research is to identify whether their integration and acceptance reflect the changing social and political changes in South Korean society. This research assumes that the degree of threat perception, democracy, and postmodern values in a country determine the overall extent of the two minority groups’ integration and acceptance in the military—in other words, a decreased threat perception, an advanced democracy, and developed postmodern values are requisite conditions for full integration and acceptance. By examining policy changes toward the minority groups, this research finds that the full integration and acceptance of these two minority groups in the South Korean military remains very limited. Although the South Korean military faces social and political pressures for improving the two groups’ integration, representation, and acceptance in the military, it does not fully respond to the pressure, as the military needs to maintain military effectiveness and unit cohesion under a high national security threat from North Korea. In South Korea, the logic of military effectiveness for counteracting the enemy seems more influential than the minority groups’ rights.