AbstractFourtyone dsRNA viruses of Cryphonectria parasitica isolates from eastern China were divided into five types on the basis of gel electrophoresis patterns. Type I contained only one segment of 12.7 kb, accounting for majority of the dsRNA viruses. Type II had another segment about 5.2 kb besides the segment of 12.7 kb, and was only found in the pathogen isolate 354. Type III possessed the 12.7 kb segment and other three small ones shorter than 2 kb, which was detected from the two isolates 238 and 250. Type IV was separated from pathogen isolates 269 and 344, which contained only two small dsRNA segments about 1.8-3.1 kb. Type V, including four small dsRNA segments about 2.6-3.3 kb and the 12.7 kb one, was only extracted from the isolate 280. The cultural characters of all these tested isolates, whether or not including dsRNA viruses, were diverse and could be also divided into five cultural types. The cultural type of C. parasitica isolate is not consistent with the type of dsRNA virus and virulence test results showed that most of the tested isolates containing dsRNA viruses were hypovirulent.