Using GMOs to solve biological problems is becoming famous now a day. Being a Muslim, we have to know about its legitimacy from Islamic Perspective. Bacteria are most commonly used genetically engineered organisms in medicines, ecological betterment, food processing, agriculture and many other fields of life. Their simple code and rapid growth make them most favourite GMOs for the service of human beings. In this regard several aspects are to be examined, 1^st of all is that whether it is a process of denaturing living organisms or this type of modification is allowed from Islamic perspective. 2^nd issue is that whether these genetically modified bacteria can transfer genes to human beings or other multicellular organisms and if we can protect living organisms from such modification. How genetic modifications can be controlled or how we can monitor such modifications? Can such genetically modified bacteria change natural equilibrium of life on earth? Such questions are discussed in the light of Qurān and Sunnaḥ in this article. Genetic modification in bacteria is surely a change in natural DNA structure of bacteria, but several human activities bring positive changes in nature and these changes are considered legitimate from Islamic perspective, however bad or negative changes are not encouraged. Hence good and bad modifications should be distinguished, good changes, sometimes, become necessary to save life on earth. The purpose of change, nature of benefits and harms, threat to nature, threat to human life, difference between medicinal, dietary or environmental use are necessary aspects in finding guidance from Islamic perspective.