The cadets hit 293 off-licences as well as 48 bars and this resulted in proceedings against 48 premises for underage sale of alcohol, three premises for underage sale of cigarettes and four premises for underage sale of knives.
There were 212 alcohol seizures, along with 6,500 cigarettes and 125kg of tobacco seized.
The volunteer cadet operation was just one arm of Operation Condor, which saw more than 4,000 officers target around 6,000 premises across the capital.
They made 360 arrests and shut down 22 premises.
Met police commander Mak Chishty, who led the operation, said: "Yet again we have seen Operation Condor bring in excellent results from our concerted efforts involving thousands of officers being deployed all over London over the past two days.
"Licensing impacts upon everyday community life Ė in our shops and supermarkets this means people do not sell knives, harmful substances or alcohol to young people; in our pubs and clubs it means that alcohol is sold and consumed in a responsible way, on our roads it means that vehicles, such as taxis are properly licensed and safe.
"These are just some examples of how licensing affects all of our daily activities, and we will continue to commit resources to this and work extremely hard with our partners to tackle these areas in the future."
It is the third time Operation Condor, one of the Metís operations focusing on specific crimes, has taken place this year.