In the fungus of hands and toenails, the thickening of the nail and its yellow color is the first signs of attention. The fungus of hands and toenails is mainly caused by Trichophyton rubrum dermatophyte. They have antifungal properties due to the components of lavender oil, geranium oil, and tea tree oil structures. Oral antifungal agents used the treatment of nail fungus can cause serious side effects, especially the liver. Therefore; topical applications have been given importance in recent years. However; in topical applications, antifungal agents have difficulties sending to the target area. Therefore; nanoemulsion technology was preferred in the study. Nanoemulsion formulations of essential oils were prepared using the ultrasonication method. Centrifugal and thermal tests were applied as preliminary stability to the formulations, the pH value, viscosity, droplet size, and polydispersity index of the formulations passing this step were measured, and organoleptic controls were performed. Antifungal efficacy and release studies were performed on the formulations F4P3-I (pelargonium), F4P3-L (lavender), F4P3-C (tea tree), and F4P3-K (mixture), which were successful as a result of all the tests. According to the study, it was concluded that F4P3-I, F4P3-L, F4P3-Ç, and F4P3-K formulations might help in the treatment of fungi.