Now a days most of the farmers around world using chemicals for controlling pathogens. This will leads to the pollute the environment. so to prevent this effect we can use the biological control. In nature there is availability of more natural enemies to control the pathogens. So we can culture those natural enemies and made it available to farmers at field level. These enemies have straight effect on target pathogens and does not leads to any environmental effect.Present days nematodes were major problem around the world. To control nematode population we isolated bio agent i.e NEMATOCTONUS ROBUSTUS from the soils of Varanasi, India. This fungus can be used for the control of Nematodes. This fungus was first time we isolated in India from the soils of Varanasi. We did the mass production of this fungus and also tested the predacity level of this fungus. The results showing by these natural enemies are good. So by using bio agents we can produce healthy and environmentally safe food.