The charity spent £3,000 on the gazebo and tables which volunteers use to raise money for veterans who have fought for their country,
The Aldridge branch of the Royal British Legion posted about the theft on Facebook on Sunday.
They said: "Sadly our brand new Gazebo and tables have stolen. This cost our branch £3,000 pounds.
"If anyone sees it or has any information please get in touch with us."
The theft has been reported to the police and Legion volunteers admitted the crime has left them upset.
They said: "We have reported it to the police. We are all very sad and upset about this, but it's the world we live in."
The Legion organised a well attended Remembrance Sunday parade earlier this month and can be seen selling poppies from the gazebo throughout Aldridge and Walsall.
This year volunteers manned the gazebo sold poppies for the Legion's Poppy Appeal outdoors with the gazebo helping shelter them from the elements.
Supporters of the Legion slammed the thieves on Facebook pointing out the branded gazebo would be hard to sell due to its uniqueness.
Doris Willis said: Well that is the lowest you can get. Whoever has taken this may just dump it as it is a very distinctive gazebo."
Michelle Wood added: "That is so sad, can't see it being any use to anyone else so hopefully you'll get it back."
Several people offered to give towards a fundraising page for the replacement for the gazebo,
However, Aldridge Royal British Legion confirmed the stolen items should be covered by insurance.