The pot farm was discovered inside a building at Hayvenhurst Ave. and Vanowen St., next to the Van Nuys Airport.
Police responded to a burglary call at the location at about 6:30 a.m. Tuesday.
Officers searching the building for suspect activity with the help of a K-9 unit discovered about 3,000 marijuana plants in the facility, about 4,000 square feet.
Detectives estimate the grow is a multimillion-dollar operation. The building is located in a commercial/industrial area next to the Van Nuys Airport.