Wholly pi-conjugated amphiphiles, 4-(24442-(4-methoxyphenyl)ethenyl)phenyl)ethenyl)benzenesulfonamide (4) and 4-(2-(4-(2-phenylethenyl)phenyl)ethenyl)benzenesulfonamide (5), were synthesized by consecutive Wittig reactions. They formed stable monolayers on water and were transferred onto quartz plates as Z-type Langmuir-Blodgett (LB) films. Maintenance of the noncentrosymmetric structures in the LB films was confirmed by reflection X-ray diffraction for 4 and 5 and by optical second harmonic generation for 4.