The liquid crystallinity of poly(N-vinylcarbazole) was studied by using powder X-ray diffraction, polarized optical microscopy, and differential scanning calorimetry. The results show that the lower molecular weight fractions of this polymer do not form a liquid crystalline phase, while the samples of sufficiently high molecular weight do form a mesophase at temperatures above the glass transition. The lowest value of the degree of polymerization for PVK to form a stable liquid crystalline phase was found to be in the range of 150 to 200, significantly higher than the value of 50 for most conventional side chain liquid crystalline polymers.