隨著亞太地區的經濟大幅成長帶動了大量的能需求，特別是天然氣。同時也吸引許多學著的投入相關的研，例如Božidar ( 2012)。本研究使用三種預測方法以及1965到2011年的歷史資料，預測中國與日本在2012到2020年的天然氣消耗量。本研究結果顯示，ARIMA模型和Holt指數平滑模型得到較高的預測值。中國在2020年的預測值分別為240 BCM 和338 BCM 而日本則是185 BCM 和252 BCM。另外的灰理論預測值則較為保守，中國為150 BCM，日本為118 BCM。 整體來說，這二個國家，在未來的各項能源消耗量中，天然氣會佔重要的角色並可能在十年內有二倍的成長。除了預測外，本研究也從結果的趨勢和國家情況，給予一些政策上和投資上的討論和建議。

The Asia-Pacific area has driven numerous energy demands by significant economic growth. Natural gas research has become increasingly important, attracting numerous scholars in recent decades (Božidar, 2012). We used 3 forecasting methodologies and statistical data from 1965 to 2011, and focused on the forecasting periods of China and Japan from 2012 to 2020. Our study results show that the ARIMA model and the Holt exponential smoothing model obtained higher forecasting values in 2020, which are 240,338 billion cubic meters (BCM) in China and 185,252 BCM in Japan; the Grey model obtained slightly conservative forecasting values, which are 150 BCM in China and 115 BCM in Japan. We also provide discussions and propose recommendations for a natural-gas development policy for China and Japan at the end.