A protein having (a) an amino acid sequence represented by SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 20, SEQ ID NO: 6 or SEQ ID NO: 8, or (b) an amino acid sequence represented by SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 20, SEQ ID NO: 6 or SEQ ID NO: 8, wherein one or more amino acids are deleted, substituted and/or added in the amino acid sequence set forth in SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 20, SEQ ID NO: 6 or SEQ ID NO: 8, and said sequence has a UDP-glucose 4,6-dehydratase activity, and/or UDP-4-keto-6-deoxyglucose 3,5-epimerase and UDP-4-keto-rhamnose 4-keto-reductase activities; and a method of producing UDP-rhamnose using the above-described protein.