PROBLEM TO BE SOLVED: To provide a welded plated steel pipe having a chemical conversion coating excellent in all of weather resistance, water resistance, discoloration resistance and coating adhesion.SOLUTION: The welded plated steel pipe is produced using an Al-containing Zn-based alloy plated steel sheet including 0.05-60 mass% of Al as a base sheet, and then a chemical conversion coating having a film thickness of 0.5-10 &mu；m is formed on the external side surface of the welded plated steel pipe. The chemical conversion coating includes: a fluorine-containing resin containing 0.05-5 mass% of hydrophilic functional groups selected from the group consisting of a carboxyl group, a sulfonic acid group and the salts thereof, and 7-20 mass% of F atoms； and 0.1-5 mass% in terms of metal of a Group 4A metal compound relative to the fluorine-containing resin.
