Abstract The transport behavior of Pt(IV) has been studied through a supported liquid membrane (SLM) containing a long-chain 8-quinolinol, LIX 26, as a mobile carrier. Platinum(IV) was extracted with LIX 26 from an HCl solution via an anion exchange reaction and stripped from the loaded organic phase by a weakly acidic solution (pH>1). Platinum(IV) was nearly quantitatively transported across an SLM impregnating 15% (v/v) LIX 26 and 10% (v/v) 1-octanol in kerosene from a feed solution of 1–2 M HCl into a weakly acidic product solution. The transport rate of Pt(IV) was related to the distribution ratio on the feed side. Platinum(IV) was efficiently enriched in the product solution with high recovery.