The Sunbury railway line is a Melbourne suburban electric railway line. It has 15 stations, and is the electrified section of the Bendigo railway within metropolitan Melbourne. Prior to the line extension to Sunbury, the line was known as the Sydenham railway line, and prior to the extension of electrification to Sydenham, the line was known as the St Albans railway line.

Suburban services usually stop all stations except South Kensington. Some daytime services originate and terminate at Watergardens. Some weekday peak services run express between North Melbourne and Sunshine, stopping at Footscray. Early morning weekend services skip Southern Cross and South Kensington. Weekday morning and weekend services run clockwise, while weekday afternoon services run anticlockwise, through the City Loop. Early morning weekend services run via (but not stopping at) Southern Cross to and from Flinders Street.