The drugs, believed to be heroin, cocaine, amphetamine and cannabis, were discovered during a search of a flat in the Drumchapel area of Glasgow at about 7pm yesterday.
Officers acting on warrant also recovered a number of firearms and ammunition as well as a six-figure sum of cash following the search of the property in Linkwood Crescent.
Police said two men, aged 46 and 47, have been arrested in connection with the operation and are being held in custody.
A report will be sent to the procurator fiscal.
It is expected the men will appear at Glasgow Sheriff Court on Friday.