She wrote: 'Kush rolled, glass full... I prefer the better things!' Kush refers to a type of cannabis found mainly in Afghanistan, Pakistan and India.
She has been spotted over the past few days puffing on a suspicious looking cigarette during her Hawaiian holiday.
And yesterday Rihanna appeared to clear up exactly what she has been smoking by quoting some lyrics from rapper Drake's song Up All Night on her Twitter page.
By the way, riri is hot...