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Summary Plants have a highly sophisticated endomembrane system that is targeted by plant viruses for cell-to-cell movement. The movement protein (MP) of Ourmia melon virus (OuMV) is targeted to plasmodesmata (PD) and forms tubules to facilitate cell-to-cell movement. Despite a number of functionally important regions for correct subcellular localization of OuMV MP has been identified, little is known about the pathways OuMV MP hijacks to reach PD. Here, we demonstrate that OuMV MP localizes to the trans-Golgi network (TGN), but not to the multivesicular body/prevacuolar compartment or Golgi, and carries two putative sorting motifs, a tyrosine (Y) and a dileucine (LL) motif, near its N-terminus. Introducing glycine substitutions in these motifs results in loss of OuMV infectivity in Nicotiana benthamiana and Arabidopsis ( Arabidopsis thaliana ). Live cell imaging of GFP-labeled sorting motif mutants shows that Y motif mutants fail to localize to the TGN, plasma membrane, and PD. Mutations in the LL motif do not impair plasma membrane targeting of MP, but affect its ability to associate with callose deposits at PD. Taken together, these data suggest that both Y and LL motifs are indispensable for targeting of OuMV MP to PD and for efficient systemic infection, but show differences in functionality. This study provides new insights into the role of sorting motifs in intracellular targeting of MPs and vesicle trafficking pathways that plant viruses hijack for cell-to-cell movement.