UBD may refer to:

• UBD, a gene which codes for the human protein Ubiquitin D
• United Baltic Duchy
• Universal Publishers (Australia)
• University of Brunei Darussalam, a university in Brunei

• Sione Tu'ipulotu
• Sione Uhatahi
• Sione Utia Katoa
• Sione Utia-Katoa
• Sione Vailanu
• Sione Vaiomo'unga
• Sione Vatuvei
• Sione Vaveni Talia'uli
• Siong Leng
• Siong Leng Musical Association
• Sion Hill Convent, Dublin
• Sion Hill (disambiguation)
• Sion Hill FC
• Sion Hill (United States Virgin Islands)
• Sionidis, Michael
• Sionists
• Sion Jones (rugby league)
• Sionna (disambiguation)
• Sionne Neely
• Sion Segre Amar
• Sion, Steve
• Sion-sur-l'Océan
• Sion sur l'océan
• Sion-sur-Mer
• Siopili Perez