Nervous necrosis virus (NNV) is a major viral panthogen infecting more than 30 species of marine fish and causing a serious threat to the aquaculture industry worlwide. It causes high mortality to newly hatched fish larvae and fish juveniles of up to three month old. The virus affects cells of nervous system resulting in cellular vacuolation and neuronal degradation in the central nervous system and retina. The infected fish showed abnormal swimming behavior but the present of NNV can only be confirmed using long and tiring histopathological method. In order overcome this problem, a reliable detection kit, time efficient and cost effective semi nested RT-PCR method derived from an innovative and creative idea is developed.