Abstract: Gas chromatographs are the main tools for performing gas chromatographic analysis. To achieve simple operation and rapid, accurate analysis, operators must possess excellent operating skills. Keywords: Gas chromatograph, operating techniques, 1. Heating Due to differences in manufacturers and quality, the methods for setting the temperature vary. For temperature setting using a microcomputer or dial selection method, the temperature is generally set directly or a suitable set temperature value is selected before heating. However, if the knob positioning method is used, there are techniques involved. 1.1 Overheat Positioning Method Adjust the temperature control knob to approximately 30°C below the operating temperature to heat the gas chromatograph. When the temperature has overheated to approximately the operating temperature, use the temperature indicator and heating indicator light to gradually adjust the temperature control knob to the appropriate position. 1.2 Step-by-Step Positioning Method Turn the temperature control knob in the direction of heating by one angle to begin heating; the indicator light will illuminate. When the temperature is basically stable, turn the temperature control knob in the same direction to continue heating. Adjust in this step-by-step manner until the temperature is constant at the operating temperature. 2. Cell Balancing Cell balancing essentially involves balancing the thermal and conductive bridge to achieve a suitable output. The adjustment techniques discussed here apply to gas chromatographs with cell balancing, zeroing, and recording zeroing functions. First, use the cell balancing or zeroing knob to adjust the recorder pointer to a suitable position. Second, reduce the self-attenuation to approximately 16 times and observe the pointer movement. Third, use the recording zeroing knob to return the pointer to its original position. Fourth, reduce the attenuation and observe the pointer movement. Fifth, use the zeroing or cell balancing knob to return the pointer to its original position.