Police have seized more than 480 cannabis plants during raids on homes in Elderslie and Campbelltown.
Officers arrested three people during the two searches.
Camden Police Area Command officers searched an Elderslie home about 4.30am on July 2.
Officers found a large-scale hydroponic set up within the home, seizing 352 cannabis plants and equipment.
A 41-year-old man was arrested and taken to Narellan Police Station, where he was charged with having a large commercial quantity of cannabis.
The man appeared at Campbelltown local court on July 2.
He was formally refused bail to reappear at the Campbelltown court on August 26.
Campbelltown Police Area Command officers also searched a home in Campbelltown on July 17.
Police stopped a vehicle on Moorebank Avenue about 8.30pm and spoke with two men - both aged 24.
Police searched the vehicle and seized more than 18 kilograms of cannabis head.
The pair were arrested and further inquiries revealed the driver was in Australia illegally.
Police also searched a Campbelltown home and seized 136 cannabis plants and equipment.
The two men were taken to Campbelltown Police Station and charged with supplying a prohibited drug; having an enhanced indoor cultivation plant for commercial purpose; using electricity without authority; and cultivating a prohibited plant.
Both men appeared at Campbelltown local court on July 18 and were refused bail. The men will appear
Immigration authorities were also notified about the illegal resident.
The Elderslie and Campbelltown home searches were made as part of a large-scale police operation into the cultivation and supply of cannabis across south-west Sydney.
Nine police area commands - including Campbelltown and Camden - searched 25 homes across the region as part of Operation Trident.
Officers seized 3742 cannabis plants, worth an estimated street value of more than $11.8 million.
South West Metropolitan Region operations manager, Detective Chief Inspector Dean Johnstone praised the combined efforts of police for their coordinated approach in addressing drug-related crime.
"Over the past month, our officers have put a significant dent in the cultivation and supply of cannabis across south-west Sydney," he said.
"Together they have removed close to $12 million worth of cannabis from our streets and these results truly are a testament to their hard work and dedication to making our community a safer place.
"Those who continue participate in illegal drug-related activity should see this as a caution - our officers will target you, charge you and put you before the courts.
"The community of south-west Sydney should be reassured that our officers, right across the region, are doing everything possible to find and arrest those that put other's lives at risk."