It is of great significance to study the fertility mechanism of rice spikelet for rice production.UDT1 and TDR genes encode bHLH transcription factors that are involved in the development of rice anther tapetum, and their functional defects lead to male sterility.The main aim of this study was to analyze the effect of UDT1/TDR gene overexpression in anther development.UDT1/TDR over-expression vectors were constructed, and overexpression transgenic plants in the variety "LJ11" background were obtained by agrobacterium-mediated transformation.The T₁ generation of transgenic plants were used for phenotype analysis, including anther morphology, pollen fertility and seed setting rates.Four UDT1-OE lines and three TDR-OE lines were identified by qRT-PCR assay and used for further analysis.The results showed that the amount of fertile pollen grains of UDT1/TDR-OE plants significantly decreased, the anther development was abnormal, and the seed setting rate significantly declined as well.We conclude that UDT1/TDR over-expression affects the development of rice anthers, decreased the proportion of fertile pollen and led to male sterility.This study further provides more evidence and supports the critical roles of UDT1/TDR in rice fertility.