A well-defined polysilsesquioxane with reactive Si-N bonds, poly(p-decyl anilino)silsesquioxane (PASQ), was successfully prepared using supramolecular template polymerization. The monomers 1,3-bis-(p-decyl anilino)-1,1,3,3-tetrachloro-disiloxanes first self-assembled into ladder superstructures (LSs) primarily through the synergistic interactions of hydrogen bonding and the van der Waals interactions, and then polymerized by adding water and triethylamine to produce a well-defined PASQ The LSs was fully characterized using vapor pressure osmometry (VPO), UV-vis spectroscopy and X-ray diffraction (XRD). NMR and XRD measurements revealed that the PASQ was a ladder polymer. The reactivity of PASQ was confirmed by its Si-N bond reacting with trimethylsilanol to form a ladder-like trimethylsiloxysilicate (LMQ). The ladder structure of LMQ was also thoroughly characterized, which further verified the ladder structural regularity of PASQ. (C) 2012 Elsevier Ltd. All rights reserved.