Sam Hunt's Fiancee All Smiles in Wedding Dress Before Ceremony

Sam Hunt's fiancee doesn't appear to have cold feet ... she's smiling from ear to ear as she prepares to wed the singer.

Hannah Lee Fowler was beaming outside her wedding venue in a stunning white dress ... and got some assistance with her train while walking in.

We broke the story ... Sam and Hannah are set to get hitched Saturday in his Georgia hometown in a very intimate affair -- close friends and fam only.