The reigning UEFA Champions League holders weathered early pressure from the Moroccan champions before taking full control of the contest.
The Gunners opened the scoring in the eighth minute when Laia Codina’s header from a Mariona Caldentey corner crossed the line after a goalkeeping error, a decision later confirmed by VAR.
Arsenal doubled their lead four minutes later, with Frida Maanum finishing from close range after fine work from teenage debutant Smilla Holmberg and Olivia Smith.
Caldentey made it 3-0 from the penalty spot following a handball, before Smith added a fourth just before half-time with a precise strike.
The Londoners continued to dominate after the break, and substitute Alessia Russo scored twice to complete the emphatic victory. They will now face Corinthians in the final, while ASFAR Rabat play Gotham in the third-place match.