Genetically modified (GM) foods are any foods obtained from plants, animals or microorganisms in which original genetic makeup is deliberately changed by using recombinant DNA technology with one or more altered characteristics. GM foods are matter of significant public controversy in many countries of the world. Many public healths related and environment related issues have been raised against the GM foods. Significant trade dispute have been experienced among different countries regarding export and import of these products. Attitudes of peoples and authorities of different countries vary regarding GM foods and their effects on health and environment. This article will try to discuss the issues raised against GM foods and reality behind those issues. Public attitudes and technical scientific knowledge about GM foods will also be discussed briefly. Safety and regulation of GM foods will also be reviewed briefly.