In a Facebook post, officers poked fun after making the helpful discovery on the Bury line of the city’s Metrolink earlier on Friday.
Posting a picture of the items recovered, they issued an urgent “appeal” for the dealer to get in touch so they could “reunite the lost property with its owner”.
Police said the grey rucksack contained: 25 tablets, a large amount of white powder, small snap bags containing white rocks, snap bags containing white powder and scales.
Amazingly, the owner also left a Community Payback card in the back complete with his name and address.
In the post, on the Greater Manchester Police (GMP) Bury South page, it said: “Police appeal to reunite lost property with its owner.
“Brilliant, first laugh I’ve had today after a hard day at work”
“A poor individual has forgotten his rucksack while travelling on the tram on the Bury line.
“Metrolink have located the bag and have checked for any identification inside to reunite the property with its owner and located; 25 tablets, large amount of white powder, small snap bags containing white rocks, snap bags containing white powder and scales.
“Thankfully the owner of the bag was helpful enough to leave his Community Payback card, his name and address.”
Many Facebook users found the case hilarious, with the post quickly racking up more than a thousand likes and 500 shares.
One commenter wrote: “I’m sure he’ll hot-foot it to the station to collect his stash!”
Another added: “Brilliant, first laugh I’ve had today after a hard day at work.”
While a third speculated if the man’s intentions had been more innocent.
“Maybe he’d just been to get ingredients to bake a lovely cake?” he asked.
Magistrates or judges can issue offenders to carry out anything from 40 to 300 hours of unpaid work as part of a sentence for this kind of criminal offence.
It comes as police and authorities in Manchester are gearing up for a weekend of huge events in the city, with Parklife festival and huge gigs by the likes of Noel Gallagher and Muse taking place.
A number of high-profile figures have admitted to taking drugs over the years.
On Friday, Prime Ministerial hopeful Michael Gove revealed he had taken cocaine multiple times.