The men's javelin throw at the 2024 World Athletics U20 Championships was held at the Estadio Atlético de la VIDENA in Lima, Peru on 27 and 29 August 2024.

[1] U20 standing records prior to the 2024 World Athletics U20 Championships were as follows: The qualification round is scheduled to take place on 27 August, in two groups, with both Group A scheduled to start at 16:20 and Group B at 17:43.

Athletes attaining a mark of at least 72.50 metres (Q) or at least the 12 best performers (q) qualified for the final.

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