As one of the most dominant asset pricing models in the field of finance, the Capital Asset Pricing Model (CAPM) is frequently used to assess the risk and expected return in project finance. Yet, this mathematical model is still lacking in studies in the field of energy commodities. In this paper, the CAPM (expected return, beta, risk-free rate, and market rate of return) and some statistical tools (mean, standard deviation, variance, and covariance) will be used to study the investment risks on expected returns of four common energy commodity ETFs (USO Oil, BNO Brent Oil, UNG Natural Gas, UGA Gasoline) from 2017 to 2021. The research findings show that those assets which have positive beta values (USO, BNO, and UGA) result in positive expected returns, and the only energy commodity ETF (UNG) that has a negative value of beta ends with a negative expected return. In addition, risks and expected returns are positively correlated to each other. This means that the larger the beta value (higher risk), the higher the expected return in general, and vice versa. For example, in this study, UGA which has the largest beta value (2.34) generates the highest expected return (0.3732), and UNG which has the smallest value of beta (-0.28) gains the lowest expected return (-0.0222) or suffers a loss in this study.