Around 1,000 marijuana plants were found during a police raid at a unit in Wednesfield.
The building in Neachells Lane was empty when police arrived and so far no suspects have been arrested in relation to the find.
Pictures from the scene showed how the warehouse had been transformed into a dedicated growing site with row upon row of potted plants growing under lights.
Air ducts had also been installed and plastic sheeting lined the walls.
Officers from West Midlands Police's dedicated cannabis disposal team were called to chop down and bag up the plants and seize the equipment.
They wrote on Twitter: "Tagging and bagging. Hard work but taking future profit from criminal hands means they can’t spend those funds on other areas of crime #DeniedFunds."
A West Midlands Police spokesman added: "We’ve recovered around 1,000 cannabis plants from an industrial unit in Neachells Lane, Wednesfield.
"They were discovered after a warrant was executed last Thursday. No-one was in the unit and enquiries are continuing."