The extraction of Pt(IV) by Aliquat 336 (R3R'N+Cl−) in dodecane modified with 4% dodecanol from hydrochloric acid solutions has been investigated. The analysis of metal distribution data by numerical calculations suggested the formation of the species (R3R'N+)2PtCl62−in the organic phase with formation constant log β=5.26±0.02. The results obtained on Pt(IV) distribution have been implemented in a solid supported liquid membrane system, being NaClO4solutions the most effective to strip the metal from the organic solution. Influence of membrane composition and metal concentration on platinum transport have also been studied.