This study aimed to investigate the beneficial effects of Lactobacillus reuteri KCTC 3594 probiotics and paraprobiotics on the moisturization and wrinkle improvement of neck skin in women in their 30s-40s. For this investigation, a total of 30 participants were divided into the following three groups (10 participants each): control group (Cont), L. reuteri probiotic group (Pro), and L. reuteri paraprobiotic group (Para). L. reuteri was administered to each group (1×1010 CFU / capsule) on an empty stomach in the morning once a day for 12 weeks. After the 12-week intake of L. reuteri, no significant change in skin moisture content was observed in the Cont group, while a statistically significant increase was detected in the Pro and Para groups (p<0.001). Regarding wrinkle improvement, no statistically significant change was noted in the Cont group, while the Pro and Para groups revealed statistically significant declines (p<0.01 and p< 0.05, respectively). The obtained results revealed the following: moisture level and wrinkles improved in the Pro and Para groups. In the Pro group in particular, positive effects on wrinkles were identified . This study confirmed that the oral intake of L. reuteri is effective at slowing down the aging of neck skin and has a positive effect on the skin. It appears that such intake produced intrinsic changes in the skin by enhancing immunity in the intestines and skin. The results of this study confirm the usefulness of L. reuteri probiotics and paraprobiotics as potential cosmetics raw materials.