Optimal investment portfolio is beneficial for investors to make decisions and construct investment strategy. This paper uses effective frontier methods to build an investment portfolio. This study selects 8 different companies from the USA, which are AMD, MRVL, LRCX, QCOM, INTC, AVGO, and TXN, and collects the data to optimize investment portfolio. The study finds that the optimal portfolio point is (0.1407, 0.0506), the risk is 0.1407, and the return is 0.0506. In this case, for AMD, MRVL, NVIDA, LRCX, INTC, QCOM, AVGO, and TXN, the weights for each company are 0.0502, -0.3867, 0.5289, 0.4367, -0.9987, -0.2805, 1, and 0.6501, respectively. The study allows for short selling and buy mechanisms, since a negative number is actually equivalent to a short sale. As a result, the study has an optimal portfolio that enables investors to make optimal investment decisions for the company the study choose. Through this research, it can help people to increase their life quality, because investment can help with more finance in the daily life, which can let people consume a better goods.