The synthesis and characterization of side-chain liquid crystalline polymetnacrylates containing fluorinated diphenylacetylenic and naph-thylphenylacetylenic side groups are presented. The phase behavior of the prepared monomers and polymers was characterized by differential scanning calorimetry, optical polarizing microscopy, and x-ray diffraction. All of the methacrylate monomers exhibit no mesomorphic behavior. Polymers which contain eleven methylene units in their spacers reveal smectic mesomorphism. Polymers with a short spacer length, i.e., three or six methylene units, present either a nematic phase or no meso-phase. The glass transition temperatures of the obtained polymers decrease as the spacer length increases. The polymers containing fluorinated naphthylphenylacetylenic side groups show a higher tendency to form a mesophase than those containing fluorinated diphenylacetylenic side groups. Incorporation of a lateral fluoro-substituent in the meso-genic core decreases not only the possibility to form a mesophase but also the thermal stability of the mesophase.