Officers unearthed the drugs den on Whitehall Road, in Palfrey, just after 7am on Wednesday.
A 24-year-old man was arrested at the scene on suspicion of being concerned in the production of a controlled drug.
A spokesman for West Midlands Police said: "We executed a drugs warrant at a premises in Whitehall Road, Walsall, just after 7am on Wednesday.
"We found a cannabis production site with approximately 200 plants within the building.
"A 24-year-old man was arrested at the location for being concerned in the production of a controlled drug."
