Investigation on precision and accuracy of gas chromatography equipped with thermal conductivity detector (GC-TCD) method for the measurement of CO2, C3H8, and CO as pollutant models at different flow rate of helium (He) carrier gas ranging from 17.50 to 36.25 ml/min were conducted. It was found that percentage of relative standard deviation (%RSD) values for both precision an accuracy show an overall gradual decrease as the carrier gas flow rates increased up to 25 ml/min. After that, the %RSD was found to increase with a further increase in the flow rate. These findings indicate that the flow rate of 25 ml/min was found to be the most precise and accurate level among all flow rates tested under experimental conditions of this study. While the %RSD values obtained at all flow rate are given in details. Consequently, our results suggest that the flow rate of carrier gas was a determining parameter for varying the precision and accuracy of the GC-TCD method. Owing to the fact that carrier gas act as a transporter of components of the mixture in the form of vapor or gas through the column, setting of the flow rate of carrier gas should in proper level achieve a precision and accuracy of the GC-TCD method. nema