The composition of natural gas plays an important role in gas processing and transportation, and the main method for determination of the composition of natural gas is gas chromatography. In gas chromatography the efficiency of separation and the selectivity are the main characteristics of the analytical process. In this work the influence of the type of packed column on separation efficiency and selectivity during chromatographic analysis of natural gas under various conditions was investigated. The highest theoretical plate number was obtained with a Porapak R 4233 column (3 m), the best symmetry of the peaks was obtained with an OPN/Porous-Sil C Column 4355 (3 m), and the highest resolution was obtained with the Hayesep Q# 1754 (3 m), Hayesep D 4741 (2 m), and Porapak Q 1723 (2 m) columns. It was shown that optimization of operation conditions can significantly improve the efficiency and selectivity of chromatographic determination of the composition of natural gas.