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<i>Pectobacterium</i> spp. infect many horticultural crops worldwide and lead to serious crop losses. Zinc-uptake-regulator (Zur) proteins are present widely in prokaryotes and play an important role in pathogenicity. To uncover the role of Zur in <i>P</i>. <i>odoriferum</i>, we constructed mutant (<i>ΔZur</i>) and overexpression [Po (<i>Zur</i>)] strains of a <i>Zur</i>, and a virulence assay showed that the Po (<i>Zur</i>) was of significantly lower virulence, while the <i>ΔZur</i> displayed significantly increased virulence on Chinese cabbage compared to their respective control strains, wild-type <i>P</i>. <i>odoriferum</i> (Po WT) and <i>P</i>. <i>odoriferum</i> harboring an empty vector (Po (EV)) (<i>p</i> < 0.05). The growth curves of the <i>ΔZur</i> and Po (<i>Zur</i>) showed no obvious differences from those of the control strains. Comparative transcriptome analysis showed that <i>Zur</i> overexpression in <i>P</i>. <i>odoriferum</i> induced differentially expressed genes (DEGs) related to flagellum and cell motility, while mutating <i>Zur</i> resulted in DEGs mainly corresponding to divalent-metal-ion transport and membrane transport. Phenotypic experiments on the Po (<i>Zur</i>) showed that flagellum numbers and cell motility were reduced in comparison with the control, while those of the <i>ΔZur</i> did not change. Collectively, these results show that the Zur negatively regulates the virulence of <i>P</i>. <i>odoriferum</i> and might function via a dual mechanism dependent on dose.