PROBLEM TO BE SOLVED: To provide a vinyl chloride-based resin composition which is excellent in tube extrusion moldability, and stickiness resistance and kink resistance of a molded tube when it is stored in a wound state, and which can provide a tube suitable for a medical application.SOLUTION: A vinyl chloride-based resin composition comprises: (a) 100 pts.mass of a vinyl chloride-based resin which satisfies the following features (1) and (2) and (b) 15 to 150 pts.mass of a diisononyl hexane-1,2-dicarboxylate plasticizer. A polystyrene-equivalent mass average molecular weight of a differential molecular weight distribution curve as measured by gel permeation chromatography is 165,000 or more and 235,000 or less ...(1). Molecular weight distribution, Mw/Mn, is 2.03 to 2.22, where Mw is a polystyrene-equivalent mass average molecular weight of a differential molecular weight distribution curve as measured by the gel permeation chromatography and Mn is a polystyrene-equivalent number average molecular weight ...(2).
