Farmers face several problems due to diseases that affect their plants. To diagnose the same, well-equipped lab is required and it is not efficient solution and not even budget-friendly. To provide all the farmers and cultivators with smartphones with internet access, we could reduce the food loss in the country. In this chapter we have covered how deep learning can be used to make an image classifier based on AlexNet. The trained weight is then deployed to classify new images according to diseases present on leaves. To train the model, we have used the dataset that contains 38 classes of different diseases. As a result, we are able to achieve 91.3% accuracy on test set using AlexNet model