Gas chromatography (GC), a technique developed by Nobel Laureate Martin and colleagues in 1952, has become an indispensable tool in various industries over the past six decades. The molecules that are volatile in nature and are not destroyed by the heat are better suited by gas chromatography. In gas chromatography, both capillary and packed columns are being used for different analysis. Different columns and their chemistry have been thoroughly discussed in this chapter. Different detectors are utilized like electron capture detector, NP detector, flame ionization detector (FID), flame photometer detector, TCD, etc. in gas chromatography. The gases that are usually used in the gas chromatography are He, N, H2, and oxygen. Mass spectrometry detectors have revolutionized gas chromatography techniques and are considered as gold standard in pesticide residue analysis. The advantages of gas chromatography include good precision and accuracy. The analysis is completed in short time, the cost of instruments is relatively low and life is generally long, and the technique is suitable for routine analysis because the operation of a gas chromatograph and related calculations do not require highly skilled person. The sensitivity of the method is quite high. It is micro-method and only few mg of the sample is sufficient for analysis.