The extraction of Pd(II) by triphenylphosphine sulfide (TPPS) in toluene from hydrochloric acid solutions containing small amounts of SCN- has been investigated. The role of thiocyanate on the Pd(II) extraction is explained as a trans-effect with the formation of mixed complexes PdCl4-n(SCN)(n)(2-), less inert to ligand substitution than the chloride complexes. The analysis of metal distribution data by numerical calculations suggested the formation of the species Pd(SCN)(2) . TPPS and Pd(SCN)(2) . 2TPPS in the organic phase with formation constants log K-021 = 13.00 and log K-022 = 14.24, respectively. A comparison of the results with those obtained using triisobutylphosphine sulfide (TIBPS) under similar conditions reveals a lower influence of SCN- concentration and also lower values for Pd(II) extraction, which can be attributed to the electron withdrawing characteristics of the aromatic ring with a decrease of the solvating power of the S atom for TPPS. The results obtained on Pd(II) distribution have been exploited in a three phases system by implementing a solid supported liquid membrane, being thiocyanate concentration the driving force of the mass transfer process. The behavior of the system is similar to that observed in the two phases.