Burkholderia cepacia （Bc） and Pseudomonas aeruginosa （Pa） are both biocontrol agents in agriculture and opportunistic human pathogens in hospitals. Effective management and utilization practice is needed to understand their characteristics and distribution in rice. During the last decade, the two opportunistic human pathogens were detected in 631 samples of rice seed and 117 samples of rice plant in plain, highland and mountainous rice growing areas of China. Bc and Pa were primarily differentiated by common bacteriological characteristics and pathogenic tests and then identified into species by Biolog and FAME tests. However, the genotypes of Bc still could not be distinguished. It has been noted that the Bc and Pa mainly existed in rice root with the highest distribution frequency in plain areas （ 6.1% and 16.1%） and lowest in the mountainous areas （1.0% and 7.8%）.
