The present study was conducted to assess poly (vinyl methyl ether) (PVME) for collecting chemical substances in water in an attempt to provide a preconcentration and separation procedure for constituent species in a urine analysis. Although PVME, a thermally reversible polymer, is soluble in water below 31°C, it coagulates upon heating at above 31°C, and becomes insoluble. With a phase separation of PVME from an aqueous solution, certain substances in solution were incorporated into the coagulated polymer. An assessment was made for some familiar substances as urine components. Collection ratios obtained were appreciable (1299.6%) for fatty acids, phospholipids and steroids. Contrary to this, inorganic cations and anions, glucose, creatinine and urea were scarcely collected in PVME PVME was thus found very useful for the preconcentration of hydrophobic substances while removing hydrophilic substances in urine sample.