The pollution of water is increasing day by day with a rapid pace and it has reached an alarming situation in this century. Although, many methods are available for wastewater treatment but majority of them are not green chemical in nature. The scarcity of useable/potable water in becoming a burning problem all over the globe. Photocatalysis has emerged as a promising technique for wastewater treatment. It can degrade some stable organic pollutants also to less harmful or harmless smaller degradation products. However, the activity of a photocatalysis is restricted by little absorption in the visible range and fast electron–hole pair recombination. These limitations can be overcome by increasing the photocatalytic activity by some modifications such as sensitization, doping, Z-scheme, use of co-catalyst, composite formation, etc. The reduction of carbon dioxide and photosplitting of water to hydrogen can also be driven photocatalytically to solve the problems of global warming and generation of hydrogen as the fuel of future. All these will be discussed in the presentation.