Fully aromatic polyesters have been prepared by esterification reaction between hydroquinon derivatives and terephthalic acid. These polymers as anticipated displayed thermotropic liquid crystal tehaviour, which was evidenced by DSC method. Also the TGA results revealed that these polymers are fairly thermally stable up to the temperature of 450℃ and beyond that the scission of ester linkage had occurred. Comparisons were made from the synthesis point of view between the fully aromatic polyester and the conventional polyethylene terephthalate. These two condensation reactions appeared similar with exception of their reaction temperatures, i. e., the latter took place at temperatures 50 to 60℃ lower. Also, the conventional type differed from the liquid crystal type in melt viscosities particularly around the temperatures where the condensation comes to completion. The conventional polyester exhibits a Newtonian behavior turns into pseudoplasticity. For the aromatic types, on the other hand, a pseudoplastic behavior sets in earlier, say, at a shear rate of 5 sec^-1 and its flow index is much lower than that of the conventional polyester. Thus at shear rates imposed by the mixing methods conventionally in practice at present, the melt viscosities of liquid crystal polymers such as ones treated herein, can be lowered significantly in comparision to those of non-liquid crystalline polymers. This supports strongly the possibility of employing conventional process equipment for the synthesis and processing of new aromatic polymer.