The 2018 IIHF World U18 Championship Division III was two international under-18 ice hockey tournaments organised by the International Ice Hockey Federation.

The Division III A and Division III B tournaments represent the sixth and the seventh tier of the IIHF World U18 Championship.

The Division III A tournament was played in Erzurum, Turkey, from 26 March to 1 April 2018.

(Further-eastern European Time – UTC+3) The Division III B tournament was played in Queenstown, New Zealand, from 26 to 28 April 2018.

(New Zealand Standard Time – UTC+12)