It is an age of nanomaterials. Nanotechnology has revolutionized the scientific world. Every sphere of technology has benefited significantly by using nanomaterials. A number of physical and chemical methods are being used for the synthesis of nanomaterials. In recent years, much emphasis is placed on green synthesis, particularly by using plant extracts or microorganisms. This is useful for promoting environmental sustainability. Microwave heating and ultrasound techniques are also being used for the synthesis of different types of nanomaterials. Green synthesis is a more advanced method of synthesizing nanomaterials over other methods because of its simplicity, lower cost, and relatively higher reproducibility. Plants produce more stable nanoparticles compared to other means, and it is straightforward to scale up. The risk of contamination is also lower. In this article, different methods of green synthesis of nanomaterials and applications have been reviewed and discussed.