This study explored the associations between bedtime stress and the hemodynamics in the prefrontal cortex (PFC) during the first sleep cycle. Stress biomarkers including salivary cortisol and sIgA were measured. Perceived stress level was rated on a 1-10 Likert scale right after the collection of the salivary samples. The hemodynamics of the pre-frontal cortex (PFC) was measured using a wearable functional near-infrared spectroscopy (fNIRS) device. Stress was found to correlate to the hemodynamics in the mid-DLPFC, the caudal-DLPFC, and the left RLPFC. The relationships between stress and these PFC subregions depends on the stress indicator adopted. Our finding provides supplementary support to the role of the PFC in processing stress.