In the recent years, the two rainbow trout viral diseases (IHN and IPN) were spread. over northeast China through import of infected eggs. IHN and IPN has now been diagnosed in four trouts farms. The first record of the IHN occurred in 1985, rainbow trout fry were infected in Bahai eaid water fish egpe mental station. Another major outbreak occurred in Benxi Rainbow Trout Farm in April 1986 where 100%of 600, 000 rainbow trout fry died in 3-15 days after the onset of the disease. IPN was first observed in Eohai Cold Water Fish Experimental Station in May 1987, and about 50,000 rainbaw trout fry died. The infection originated from eggs which were imparted from Japan.