Michael Douglas -- I'M STILL MARRIED!!

Michael Douglas is still sporting his wedding ring ... and wants everyone to know he's STILL MARRIED to Catherine Zeta-Jones, despite reports he split from his wife.

Douglas was in Berlin over the weekend for the premiere of his movie "Behind the Candelabra" ... when a reporter asked him why he was still wearing a ring on his wedding finger.

Michael's response -- "I'm married."

Just last week, reports surfaced that Douglas and Zeta-Jones were taking a break after 13 years together ... and the break was, in part, due to the stress from Douglas' battle with cancer and Catherine's struggle with bipolar disorder.