As an obligate biotrophic fungus, Puccinia striiformis (Pst) forms a specialized infection structure-haustoira during infection, which involves in the exchange of nutrients between host and pathogen.Cytological studies revealed that rust fungi secreted sets of effectors from haustoria to host cells to regulate the physiology and metabolism of host cells, thus to promote the infection and colonization of pathogens, but little is known about the mechanisms by which the effectors enter into and function inside plant cells to cause the stripe rust disease.Therefore, in this study we intended to identify the Pst effectors in large-scale from the accomplished Pst haustoria transcriptome, analyze their expression profiles and inter-specific polymorphism and define their sub-cellular localization.Among the predicted secreted proteins from Pst haustoria transcriptome, fifty were tested in tobacco cells through Agrobacterium infiltration and two were identified to be able to suppress cell death caused by mouse pro-cell death protein Bax,designated as PsEchl and PsEch2.QRT-PCR analysis showed that both of the candidate effectors PsEch1 and PsEch2 were significantly induced during Pst infection.Meanwhile, PsEch1 and PsEch2 exhibited low polymorphism among 8 Pst physiological races with different virulence, indicating that they were relatively conservative in evolution of Pst.Transient expression of effector-eGFP fusion protein in tobacco cells through Agrobaterium infiltration revealed that both PsEch1 and PsEch2 were localized in cytoplasm while the signal peptides leading GFP outside of the cells, indicating that the two effectors were firstly secreted out of the cells, and then can re-entry into plant cells in the absence of Pst.