Abstract: Red body disease occurred on a large scale in the shrimp farm in Liaoning Province in July, 2001. The characteristics of red body disease were observed by the authors. Infected animals displayed red bodies, sluggish swimming, disgusted feeding, hard shell and high mortality. Three bacterial strains were isolated from the muscles of the diseased Litopenaeus vannamei. In artificial infection test, one of them was proved to be the pathogen, numbered 0107. According to the traditional biochemical identification and 16S rRNA gene homology analysis, the pathogenic bacteria were Vibrio parahaemolyticus. Drug sensitivity test showed that the pathogenic bacteria are highly sensitive to cefoperazone, ceftriaxone, etc., while not sensitive to ampicillin and benzylpenicillin.