In this study, five types of yogurt samples were produced with different concentrations (0% [control group], 0.05%, 0.10%, 0.15%, and 0.20%) of Mentha pulegium L. (pennyroyal) powder (MPP) and their physicochemical, textural, sensory, and microbiological properties were investigated on the 1st, 7th, and 14th days of storage. Increasing concentrations of MPP affected the L* and a* values of yogurt considerably. About 0.05% and 0.15% MPP addition improved the textural properties of yogurt samples. The higher the MPP concentration, the lower the lactic acid bacteria counts were; however, the numbers were still over the minimum requirement for yogurt. Fibrous and filamentous structures in yogurt samples with MPP were monitored by scanning electron microscopy. Consequently, it can be stated that MPP can be successfully added to yogurt. Furthermore, considering sensory evaluations, it would be plausible to say that yogurt samples containing MPP up to 0.10% may have market potential in the future.