The peculiarity of a series of side-chain liquid crystalline polymers with mesogenic units attached directly in a side-on mode was studied by using nuclear magnetic resonance, wide-angle X-ray diffraction, polarizing microscopy and molecular simulation techniques. It was found that in special cases molecules of side-chain liquid crystalline polymers may become rather rigid as a whole and take the more extended conformation, like a rod with the main chain approximately parallel to the rod axis. The side-chain mesogens are packed around the main chain with their axes almost perpendicular to the main chain. These side-chain polymers may exhibit behaviour similar to that of main-chain polymers. The effect of interaction between main-chain and side-chain mesogens on the mesophase formation of side-chain polymers and the influence of mesogen location in molecules on the behaviour of liquid crystalline polymers are discussed.