Officers conducted the raids in the city on Wednesday morning (August 1).
At the first address in Hanover Terrace a quantity of class A drugs, believed to be crystal meth, were discovered and seized by officers, said Sussex Police.
Officers also entered an address in Stone Street, Brighton, and three men were discovered inside the flat.
A significant amount of class A drugs and paraphernalia were discovered in the property, alongside around £5,000 in cash, said police.
Two Brighton men, aged 44 and 52, were arrested on suspicion of possession with intent to supply a Class A drug.
A further man, aged 48 from Brighton, was arrested on suspicion of possession of a class A drug and the conspiracy to supply a class A drug, said police.
All three have been released under investigation.
Detective Constable Jane Walker from the Brighton Community Investigation Team said: “Drugs including what we believe to be crystal meth were seized during these raids, which means they won’t be on the streets during this weekend’s celebration in the city.
“We work hard to take drugs off the street to keep Brighton and Hove safe.”
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