SD1

SD1 or SD-1 may refer to:

• South Dakota's 1st congressional district, a United States electoral district
• British NVC community SD1, the only shingle community in the British National Vegetation Classification system
• MSD SD-1, a floppy disk drive station for Commodore computers
• Panasonic HDC-SD1, a digital camcorder
• Sigma SD1, a digital SLR camera
• Rover SD1, a British car built between 1976 and 1986
• Spacek SD-1 Minisport, a Czech amateur-built aircraft design
• Northrop SD-1 drone, a battlefield reconnaissance drone of the 1960s
• SD1 (gene), a gene that may be part of the agricultural weed syndrome of Oryza sativa and O. rufipogon weeds