The secretion of adrenal stress hormones in response to acute stress is known to affect learning and memory, particularly for emotionally arousing memory material. Here, we investigated whether stress-induced modulation of [earning and memory performance depends on (i) the conceptual relatedness between the material to be learned/remembered and the stressor and (ii) the timing of stress exposure versus learning phase. Participants (earned stressor-related and stressor-unrelated words of varying arousal 1 h prior to, immediately following, or 2 h after exposure to the Trier Social Stress Test (all groups n = 16). Twenty-four hours later, delayed free recall was assessed. Cortisol and alpha-amylase were sampled to evaluate if concurrent stress-induced raised glucocorticoid levels and high adrenergic activity are implicated in modulating learning performance. Our results demonstrate that immediate and delayed post-stress learning selectively enhanced the learning and delayed recall of stressor-related high arousing words. This enhancing effect was strongly associated with concurrent stress-induced cortisol and sympathetic activity. Our data suggest that when to-be-learned information is conceptually related to a stressor and considered important (i.e., arousing) by the individual, learning under stressful circumstances results in improved memorability afterwards.