Abstract: One hundred and eighty-six isolates of Rhizoctonia spp. were obtained from tissues of rice sheath blight in 36 counties of Guangxi Province. According to the hyphal fusion with international standard isolates of anastomosis groups (AGs) of Rhizoctonia, the multinucleate series belong to R. solani AG-1 IA and AG-4, and the binucleate series belongs to AGBb. The frequency was 96.5%, 2.15 %, 1.6 %, respectively. The mycelia growth rates were different among the various Ags. The growth rate of the isolates of AG-1-IA was the highest, and the isolates of AGBb were the lowest.