West Midlands Police confiscated around 140 plants from a property in Oak Road, West Bromwich, on Tuesday night.
The average street value of a cannabis plant is £1,000. No arrests have been made.
A spokesman for the force said: "We've seized around 140 plants after a cannabis factory was discovered in Oak Road, West Bromwich. Enquiries are ongoing."
Photographs from the scene dozens of plants packed tightly together, growing under artificial lights.
An officer was also pictured with a tool used to knock down doors.
A door was also seen with a large chunk having been taken off.