AbstractBackgroundBoth topical and oral probiotics are becoming widely used. There is increasing interest in the cosmetic potential in topical probiotics. Nitrosomonas eutropha is an ammonia‐oxidizing bacteria.AimThe purpose of this study was to assess whether there is any improvement in facial wrinkles with the use of Nitrosomonas eutropha, a topical probiotic.MethodsIn this prospective study, high‐resolution photographs were obtained in twenty‐nine participants at baseline and after using topical Nitrosomonas eutropha for seven days.ResultsThere was a significant difference in wrinkle depth and severity in the high concentration probiotic group. There was also a statistically significant improvement in pigmentation of the forehead and glabella in the higher concentration group.ConclusionsNitrosomonas eutropha may have aesthetic benefits in terms of reducing the appearance of wrinkles. Larger studies with longer treatment and follow‐up periods are required.