To provide an expandable and contractible motor-driven curtain rail.

An expandable and contractible motor-driven curtain rail 1 includes: a driving runner 4 fitted to hollow housings 21, 31 of an outer rail part 2 and an inner rail part 3 to be expandable and contractible in the total length, and loaded with an electric motor to be driven to travel by the electric motor; and a driven runner 5 traveling according to the travel of the driving runner 4. The curtain rail includes: first and second parallel power feeding members 22, 23 extending in the longitudinal direction in the housing 21 of the outer rail part to feed power to the electric motor of the driving runner 4 located at the outer rail part 2; and third and fourth parallel power feeding members 32, 33 extending in the longitudinal direction in the housing 31 of the inner rail part 3 to feed power to the electric motor of the driving runner 4 located at the inner rail part 3. The first and second power feeding members 22, 23 and the third and fourth power feeding members 32, 33 are respectively disposed not to abut on each other in the fitting parts.