Second-order nonlinear optical (NLO) materials have played a very important role in laser technology since the invention of laser. The materials have been developed from inorganic crystals to organic molecules and polymers. Search for new second-order NLO materials with better performance has continuously been in the frontier of material science and optical engineering. We recently have conducted systematically research in this field, and here, we would like to present some new design strategies for second-order NLO polymers, including dendronized polymers, dendrimers and hyperbranched polymers with a new concept of “suitable isolation group”. Also, we will present the synthesis and characterization of a new kind of polymer: “dendronized hyperbranched polymers”.