This meta-analysis of 58 resting baseline studies, 25 startle studies, 17 standardized trauma cue studies, and 22 idiographic trauma cue studies compared adults with and without posttraumatic stress disorder (PTSD) on psychophysiological variables: facial electromyography (EMG), heart rate (HR), skin conductance (SC), and blood pressure. Significant weighted mean effects of PTSD were observed for HR (r = 0.18) and SC (r = 0.08) in resting baseline studies; eyeblink EMG (r = 0.13), HR (r = 0.23), and SC habituation slope (r = 0.21) in startle studies; HR (r = 0.27) in standardized trauma cue studies; and frontalis EMG (r = 0.21), corrugator EMG (r = 0.34), HR (r = 0.22), and SC (r = 0.19) in idiographic trauma cue studies. The most robust correlates of PTSD were SC habituation slope, facial EMG during idiographic trauma cues, and HR during all study types. Overall, the results support the view that PTSD is associated with elevated psychophysiology. However, the generalizability of these findings is limited by characteristics of the published literature, including its disproportionate focus on male veterans and neglect of potential PTSD subtypes.