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Metallothionein (MT) proteins are low molecular mass, cysteine-rich, and metal-binding proteins that play an important role in maintaining metal homeostasis and stress response. However, the evolutionary relationships and functional differentiation of <i>MT</i> in the <i>Oryza</i> genus remain unclear. Here we identified 53 <i>MT</i> genes from six <i>Oryza</i> genera, including <i>O. sativa</i> ssp. <i>japonica</i>, <i>O. rufipogon</i>, <i>O. sativa</i> ssp. <i>indica</i>, <i>O. nivara</i>, <i>O. glumaepatula</i>, and <i>O. barthii</i>. The <i>MT</i> genes were clustered into four groups based on phylogenetic analysis. <i>MT</i> genes are unevenly distributed on chromosomes; almost half of the <i>MT</i> genes were clustered on chromosome 12, which may result from a fragment duplication containing the <i>MT</i> genes on chromosome 12. Five pairs of segmental duplication events and ten pairs of tandem duplication events were found in the rice <i>MT</i> family. The Ka/Ks values of the fifteen duplicated <i>MT</i> genes indicated that the duplicated <i>MT</i> genes were under a strong negative selection during evolution. Next, combining the promoter activity assay with gene expression analysis revealed different expression patterns of <i>MT</i> genes. In addition, the expression of <i>OsMT</i> genes was induced under different stresses, including NaCl, CdCl₂, ABA, and MeJ treatments. Additionally, we found that <i>OsMT</i> genes were mainly located in chloroplasts. These results imply that <i>OsMT</i> genes play different roles in response to these stresses. All results provide important insights into the evolution of the <i>MT</i> gene family in the <i>Oryza</i> genus, and will be helpful to further study the function of <i>MT</i> genes.