A new TTF derivative tetrakis(hexadecylthio)-tetrathiafuivalene (THT-TTF) as a Langmuir-Blodgett film material is synthesized. The molecular behavior at the air-water interface is studied by admixture different molar numbers of stearic acid (SA) and a possible molecular reorganization is discussed according to the occupied area per THT-TTF molecule at different SA molar numbers. THT-TTF molecules form dimers, monolayer and intermediate. The ultraviolet (UV) spectra prove this point quantitatively. After iodine oxidation, THT-TTF is not oxidized completely to the cation radical THT-TTF+ from Raman spectra. The formation of triiodide chains has been proved by Raman spectra and UV absorption spectra. Intercalation of the triiodide chain in the bilayers induces the alkyl chains rearrangement and a large reduction in layer thickness. The investigation of conductivities shows that the conductivities are proportional to the THT-TTF molar fraction and that there is a small percolation threshold at PHI* = 0.50, which means that THT-TTF is a 2D molecular system. The maximum conductivity reaches 0.9 S cm-1.