Medical articles made of a resin composition comprising a polyvinyl chloride and a tetracarboxylic tetraester are provided. As examples of the tetracarboxylic tetraester are mentioned tetra(2-ethylhexyl) 3,3',4,4'-biphenylethertetracarboxylate, tetra(2-ethyl-hexyl) 3,3',4,4'-biphenyimethane- tetracarboxylate, tetra(n-dodecyl) 2,3,3',4'-biphenyl-1,1-ethanetetracarboxylate, tetra(2-ethylhexyl) 3,3',4,4'-biphenyl-2,2-propanetetracarboxylate and the like. The tetracarboxylic tetraester is incorporated in an amount from 20 to 120, preferably from 30 to 100 parts by weight per 100 parts by weight of the polyvinyl chloride. As dissolution and migration to the surface of the article of the plasticizer tetracarboxylic tetraester are low in the medical articles, said medical articles produce no adverse effects upon body fluids such as blood when contacted. Examples of preferred medical articles are blood preservation vessels, catheters and blood transfusion sets.