Nouns ending in -sion are feminine.
The suffix forms abstract nouns of action or state.
Is passion masculine or feminine?
lapassion
The rule behind it
100% of -sion nouns are feminine
In context
Sa passion pour la musique ne diminuera jamais.
Music is his abiding passion.
Elle a une grande passion pour les antiquités.
She has a great love for antique goods.
Vous avez vraiment une passion pour la nourriture.
You really have a passion for food.