Brain activity associated with pain perception has been revealed by numerous PET and fMRI studies over the past few decades. These findings helped to establish the concept of the pain matrix, which is the distributed brain networks that demonstrate pain-specific cortical activities. In this study, we applied four levels of pain stimuli to 22 subjects and measured brain activity, biological signals (continuous blood pressure, photo-plethysmogram, and electrocardiogram), and subjective evaluation in an fMRI environment. We then calculated the peripheral arterial stiffness β_art of the fingertip from the measured biological signals, which is an index of peripheral sympathetic nerve activity. Subsequently, we identified brain regions in which the activities covaried with β_art using parametric modulation analysis. The analysis result demonstrated that the lateral and medial prefrontal cortex and ventral and dorsal anterior cingulate cortex, which are included in the pain matrix, showed activities positively correlated with β_art (r = 0.47, p < 0.001). β_art was also significantly correlated with self-reported pain intensity (r = 0.44, p < 0.001) and applied pain intensity (r = 0.43, p < 0.001). These results indicate that peripheral arterial stiffness can be used as an objective pain evaluation metric.