The Nova Scotia U18 Major Hockey League (NSU18MHL, formerly NSMMHL) is a Nova Scotian ice hockey league for Major AAA players under 18 years old.

It is a part of and follows the regulations set by the Hockey Nova Scotia organisation.

[2][3] Successful players in this league often go on to play in the MHL and QMJHL.

[5] It was founded to offer an opportunity for under 18 players from the Maritimes to compete at the highest possible level for their age group, with many associations spinning off their AAA teams to play in the broader Nova Scotia league.

For the 2019–20 and 2020–21 seasons no league champion was crowned due to the finals being cancelled by COVID-19 pandemic related lock-downs.