Police stopped a car on Garscube Road, Glasgow, at around 5.15pm yesterday and found £250,000 of heroin.
Two men, aged 19 and 24, were arrested in connection with the find.
A second recovery came around five hours later when police stopped and searched a lorry on the M74 northbound at Elvanfoot, South Lanarkshire.
Officers discovered cannabis with a street value of £297,000 in the vehicle and arrested a 49-year-old man.
It follows two arrests and the seizure of £100,000 of drugs in Fife on Tuesday.
Police stopped a car as it travelled north on the M90 and recovered half a kilogram of diamorphine and half a kilogram of cocaine from the vehicle.
Officers then searched several houses in the east Fife area under the Misuse of Drugs Act and discovered a cannabis cultivation, cocaine and £3,000 in cash.
The total street value of the drugs seized was in excess of £100,000.
Two men, aged 28 and 33, were arrested by officers in connection with those seizures.
Police said the seizures were not connected and were the result of separate intelligence-led operations.
A report is to be sent to the procurator fiscal.
Detective Inspector Graeme Lindsay, from Police Scotland Organised Crime and Counter Terrorism Unit, said: "These recoveries clearly demonstrate our ongoing commitment to ridding our communities of drugs and tackling drug-related crime.
"I would also like to reassure people that we will continue to take robust action on anyone involved in the supply of drugs, and we will act on all the information we receive.
"Of course, the community plays a vital role in this, and I would urge anyone with any concerns about drugs in their local area to contact Police Scotland on 101."