Gather all ingredients.
Combine vanilla wafers, nuts, ¾ cup confectioners' sugar, and cocoa in a large bowl.
Mix in rum and corn syrup until well combined.
Shape dough into 1-inch balls; roll in confectioners' sugar to coat.
Store rum balls in an airtight container for 2 to 3 days to develop flavor. Roll them again in confectioners' sugar before serving.
