The New York-based group said Iran had executed at least 17 juvenile offenders since the beginning of 2004, including two so far this year.
"Iran holds the deplorable distinction of leading the world in juvenile executions, and the authorities should end this practice at once," Clarisa Bencomo, the group's Middle East children's rights researcher, said in a statement.
The group said international treaties ratified by Iran prohibited the death penalty for crimes committed by people under the age of 18.
It said Sudan, China and Pakistan were the only other countries known to execute juvenile offenders.
RFE/RL Iran Report
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