This study investigated the relationship between children's proneness to endorse moral disengagement mechanisms and their anticipated antisocial lie telling. Participants were 107 predominantly white Australian children in Grade 1 (27 boys, 27 girls; M[subscript age] = 6.69 years) and Grade 4 (24 boys, 29 girls; M[subscript age] = 9.69 years). Children completed a lie-telling moral disengagement scale and two vignettes. In the first vignette, a child character witnessed a transgression and was coached to say that they did not see the transgression occur (lie type: false denial). In the second vignette, a child character did not witness a transgression and was coached to say that they saw a transgression (lie type: false allegation). In accordance with social cognitive theory predictions, greater proneness to using moral disengagement mechanisms was associated with children's anticipated lie telling for both false allegations and false denials. These findings highlight the important role of moral disengagement in children's lie telling.