The new ferrocenyl allylic thioethers FcCH=CHCH2SR (2a-e) and FcCH(SR)CH=CH2 (3a-e) (R = Ph, a; 2-naphthyl, b; 3,5-C6H3Me2, c; iPr, d; tBu, e) were synthesized in good yields from the ferrocenyallylammonium salt [1] + Iand the corresponding thiol RSH. With sufficiently strong bases to fully deprotonate the thiol, good to excellent regioselectivities (88-99%) in favor of the linear isomer 2 were obtained. The molecular structures of 2a and 2b were obtained by X-ray diffraction on monocrystals. A mechanistic proposal based on experimental data and supported by calculations is also presented, underlying the role of the base in the reaction regioselectivity.