In this study, P84-based carbon tubular membranes were fabricated and characterized in terms of their structural morphology and gas permeation properties, by using Scanning Electron Microscopy (SEM) and pure gas permeation system, respectively. The polymer tubular membranes were then carbonized under nitrogen atmosphere at different carbonization temperatures of 600, 700, 800 and 900 °C, with heating rate of 3°C/min and thermal soak time of 30 minutes. The manipulation of carbonization temperatures was required to see if it could enhance the permeation properties as desired. Pure gas permeation tests were performed using CO2 and CH4 gases. The CO2 /CH4 selectivity was found increasing as the carbonization temperature was increased from 600 to 800 °C. The carbon membrane carbonized at 800°C showed the most promising result for CO2 /CH4 selectivity, rendering 69.48 and CO2 permeance of 206.1 GPU.