This study aimed to evaluate the contact activity of the essential oil derived from Mentha piperita L. (Lamiaceae) against two significant stored product pests, namely Tribolium castaneum (Herbst, 1797) (Coleoptera: Tenebrionidae) and Sitophilus granarius (Linnaeus, 1758) (Coleoptera: Dryophthoridae), in a controlled laboratory setting. For this purpose, concentrations of 0.05, 0.1, and 0.15 µl/insect of plant essential oil were applied to stored product pests using a microapplicator. Dead insects were counted at 24, 48, 72, and 96 hours after application. As a result of the study, the essential oil demonstrated contact activity at varying rates depending on the applied pest and dose. After 24 hours, the 0.15 µl/insect application dose was the most effective against T. castaneum, resulting in a 23.6% mortality rate; after 96 hours, this rate increased to 33.4%. The essential oil exhibited greater contact activity on S. granarius, resulting in a 93.4% mortality rate after 24 hours when administered at a concentration of 0.15 µl/insect. At the end of 96 hours, the mortality rate at the same dose was found for S. granarius to be 98.2%. In addition, the effect of essential oil on the germination power of wheat grain was examined at doses of 2, 5, 10 and 20 μl/Petri under laboratory conditions. 73.8% of the seeds germinated at the maximum dose of 20 µl/Petri, while 99.4% germinated at the minimum dose of 2 µl/Petri. The research findings indicate that the essential oil of M. piperita possesses the capacity to be employed for the management of S. granarius.