Abstract: Rice grassy stunt virus (RGSV) in tropical and subtropical areas can cause large losses in rice production and quality. RGSV-infected rice plants show root disorders and the molecular mechanism is still unclear. The transcript levels of root development related genes OsPHR2, QHB, OsRR1, OsEXPB5, Crl-5 and OsEXPA17 in rice plants infected with RGSV versus control rice plants were determined by using real-time quantitative reverse-transcription PCR. The results showed that RGSV infection led to reducing transcript levels of OsPHR2 and Crl-5 genes and the relative expressions reducing rate of OsPHR2 and Crl-5 genes were 2.18 and 4.86, respectively. RGSV infection did not alter the transcript levels of QHB, OsRR1, OsEXPB5 and OsEXPA17 genes whose relative expression levels were 1/1.49, 1.01, 1.39, 1/1.37, respectively. These data suggested that RGSV could cause root disorders by regulating transcription levels of root development related genes directly or indirectly.