The game was initially pushed back from 12pm to 12.30pm, before being called off altogether.
It was a significant error from the team bus, and the side would have wanted to play against Brighton, who are 11th in the under-18s league, having won just one of their eight matches so far.
While Arsenal are in mid-table and would have wanted to secure a win following a 3-3 draw at Crystal Palace in the previous match.
Arsenal under-18s are currently unbeaten in their last four matches, and ahead of the match were five places and six points ahead of Brighton.
While Brighton had not enjoyed such a good start to the under-18s Premier League, they would have looked to the match to change their fortunes having beaten Arsenal 3-1 in February.
The senior side travel to Newcastle for their Premier League clash on Saturday at 5.30 pm.