The immense population growth around the world has put a large pressure on earth for cereal production ever increasing demand of food and climatic change has worsen the situation even more. In this scenario Crop diversification and intensification are feasible solution for growing demand of food and to fight against global warming, with technical advancement in agricultural, crop diversification and intensification are area of growing interest among the researcher. Agricultural scientist and researcher find these techniques especially beneficial to marginal farmers who depend on one or two crop in a season and in development economy where growing population and land productivity remains the critical issue. The present study focuses on different type of crop diversification and intensification technique used worldwide also on different researcher done on above mentioned issue. The present study has extensively review the work previously done on effect of two factors on overall productivity of crop. The present work will prove to be beneficial to the academician and researcher as they will know the amount of work done on the issue as well as new avenue of research, and for policy maker and industry people to know the where to invest to give benefits to the farmers and how the good policy can increase productivity without adverse effect on land.