Officers from West Midlands Police raided the property in Walsall after receiving reports of a suspected cannabis factory after gaining a warrant.
More than 300 cannabis plants with an estimated street value of £300,000 were found in the raid of Friday, September 10.
Images released by the police show multiple plants under artificial lights with wires hanging overhead.
A spokesman for St Matthews Police tweeted: "Following reports regarding a suspected cannabis factory, officers from Team 2 conducted a successful warrant.
"Over 300 plants were found.
"Thanks to Delves Police and WS Taskforce for the assistance."