Wheat (Triticum aestivum L.) is a major cereal crop essential for global food security, yet its productivity is severely constrained by diverse diseases caused by fungi, bacteria, viruses, and nematodes. These pathogens reduce yield, grain quality, and farmer income, particularly under favorable environmental conditions. Major fungal diseases such as rusts and Fusarium head blight, bacterial leaf streak, Karnal bunt, viral mosaic diseases, and cereal cyst nematodes significantly affect production worldwide. This manuscript reviews major wheat diseases, their symptoms, and impact, and presents a general methodological framework for disease assessment and management to ensure sustainable wheat production under changing climatic conditions.