Needle‐like poly(aniline p‐toluenesulfonic acid) complex aggregates were synthesized by oxidative polymerization, yielding conductivities of up to 3 S · cm−1 and maximum aspect ratios of 26. Rod‐like aggregates as precursors to be developed into needle‐like aggregates were obtained with 1 to 2 h APS addition time at 15 °C. Flake‐like polyanilines were prepared at −2 or +20 °C with 1.9 to 2.5 h of APS addition time, giving aspect ratios of 2 to 10. Plate‐like polyaniline aggregates emerged when xylene was added, and an optimum xylene concentration was 15 vol.‐%, giving 1.3 S · cm−1 conductivity. The polyanilines were characterized by optical microscopy, SEM and UV‐vis/NIR spectroscopy.