Traditionally, women's field hockey players have worn skirts, but proponents for change say wearing a skirt can be uncomfortable.
The vote comes after one player, Kaity Cooper, got into trouble when she defied the skirt-only rule during a game last fall.
She says she was told to leave the field, and threatened with a suspension for her fashion faux pas.
But instead of letting individual players decide, as Cooper had hoped, the association left the choice up to individual teams.
Cooper said she has mixed feelings about the association's decision.
"This was an incremental change and that is positive," she said.
"Individuals are still going to have to approach their teams or clubs and convince everyone to support them and that is not something that all of women would be in a position to do."
Mary Jung, a UBC assistant professor who specializes in exercise psychology, says whatever the decision, all team players should wear the same type of uniform to avoid performance issues.
"It's all or nothing and that's just because of group cohesion of wearing the same uniform and sticking together and being together," Jung said last week.
This season is almost over, so teams will have to decide on skirts vs. shorts before they take to the field again in September.