Background: Harmful alcohol use and alcohol use disorders (AUD) are major public health issues. Alcohol craving plays a central role in AUD by increasing the likelihood of consumption. While stress is a known trigger for craving, most evidence comes from observational or clinical studies. This study aimed to investigate the causal effect of experimentally induced stress on alcohol craving. Methods: Two hundred and eighty-eight healthy young men were randomized to either the Trier Social Stress Test or a control condition. Alcohol craving was assessed before and immediately after the task. Stress reactivity was measured via mood scales and biological (salivary cortisol and alpha-amylase) markers. Latent mixture modeling explored variability in the effect of stress exposure on craving, and latent group differences were examined in relation to habitual alcohol use, self-control, anxiety, depression, and emotion dysregulation. Results: Participants exposed to the stressor reported higher poststress craving compared with controls (b = 2.35, 95% CI [0.54, 4.16], p = 0.011). Within the stress group, greater mood changes (b = −0.53, 95% CI [−0.82, −0.24], p < 0.001) and biological (alpha-amylase) stress reactivity (b = 0.01, 95% CI [−0.02, 0.04], p = 0.391) were associated with increased craving. Two latent classes emerged: one (51.4% class membership) showed a positive effect of stress on craving (stress-related craving increase class [SCI]) (b = 5.37, p = 0.002), while the other (49.6%) showed a negative effect (stress-related craving decrease class [SCD]) (b = −2.70, p = 0.012). The SCI class was characterized by higher anxiety and depressive symptoms, greater emotion dysregulation, and lower self-control compared with the SCD class. Conclusions: Experimental stress can increase alcohol craving, particularly in individuals with certain psychological profiles. Craving was linked to subjective and biological stress reactivity. These findings highlight the importance of individual differences in stress responses and provide targets for more personalized studies on stress-related craving and alcohol use.