The Ryonggang Line is a non-electrified standard-gauge secondary line of the Korean State Railway located entirely within Namp'o Special City, South P'yà Ângan Province, North Korea, running from Ryonggang on the P'yà Ângnam Line to Mayà Âng. The line connects to the Husan Line to Yangmak at Husan.
The Ryonggang Line was originally opened as the Yonggang Line by the Chosen Government Railway (Sentetsu) prior to 1937.
Most freight on the line is outbound from a mine at Mayà Âng and a granite quarry on the Husan Line.
A local train, 734, operates on the entirety of this line from Mayà Âng to Ryonggang, continuing on to Kangsà  on the P'yà Ângnam Line, with a scheduled travel time of two hours fifteen minutes according to the 2002 timetable; the return trip is train number 733, taking two hours to make the trip.
A yellow background in the "Distance" box indicates that section of the line is not electrified.