The adsorption isotherm of the nonionic surfactant Triton X-100, tryptophan and BSA on temperature-sensitive poly (vinylmethylether) gel (PVMEG) was investigated for adsorptive separation of bio-related substances, The adsorbed amount of Triton X-100 on PVMEG was almost independent of pH, and comparable to that of commercial polymeric adsorbents, Tryptophan or BSA was hardly adsorbed on PVMEG, Triton X-100 was preferentially adsorbed on PVMEG from a mixed solution containing the three adsorbates, Temperature-swing adsorption of Triton X-100 was effectively carried out with a temperature span of 6 K, Adsorption and desorption rates were much accelerated by widening the temperature span, The high potentiality of separation of nonionic surfactant from bioproducts by temperature-swing adsorption with PVMEG was confirmed.