Previous research has found that both explicit and implicit reminders of one's mortality provoke hostile reactions to those who threaten one's worldview, but do not create conscious negative affect or electrodermal arousal. This study was conducted to investigate subtle affective reactions to subliminal death primes as indexed by measures of facial electromyography (EMG). Fifty-four participants were exposed to masked presentations of either the word “dead” or “pain,” and then to a worldview threatening essay. Facial EMG was recorded throughout. Analyses found the expected increase in worldview defense following mortality primes. Analyses also uncovered a novel finding with greater corrugator EMG specifically during exposure to the subliminal death but not subliminal pain primes, pointing to the sensitivity of facial EMG to unconscious cognition. However, there was little evidence for a mediating role of affect on worldview defense following exposure to death primes. Implications for understanding terror management processes and the effects of unconscious cognition on emotion are briefly discussed.