Most of those there told Premier they were LGBTI Christians who were unhappy at the decisions made at the meeting.
The US Episcopal Church has been side-lined following the meeting organised by the Archbishop of Canterbury.
It's being punished for its support of gay marriage.
One of the protestors told Premier she was there because she wanted the primates to know LGBTI Christians have rights.
She said: "They should at least also give us a chance and hear us out so we can speak, because we can speak for ourselves.
"We don't need them to make decisions. We should also be a part of what is taking place."
The group were carrying banners which said "preach love, not hate, to LGBTI people" and "In solidarity with the Episcopal Church".