Abstract: This study aims to test and analyze the influence of Herding Behavior, JCI Return, and Fed Fund Rate on the dependent variable, namely Foreign Portfolio Investment which is proxy for Total Foreign Buying. The control variables used are Gross Domestic Product, Market Capitalization, and Inflation. Sample The data used in this study is a time series data, which is data grouped based on a specific time in the form of a monthly from 2018-2023. The data used was obtained from various sources, including Bank Indonesia, the Financial Services Authority (OJK), the Jakarta Stock Exchange (IDX) and the Central Statistics Agency (BPS). This study uses individual time effect panel data regression processed using Eviews 13. In addition to using Time-Effect with panel data, the application of the Chow test in the research period (2018-2023) will be divided into 3 sub-periods, namely the 2018-2019 sub-period, the 2020-2021 sub-period, and the 2022-2023 sub-period of 24 months each. The results of the research obtained, Herding Behavior, Market Capitalization and Inflation have a positive and significant effect on Foreign Portfolio Investment as measured by Total Foreign Buying. JCI Returns, Fed Fund Rate, and Gross Domestic Product have a negative and significant effect on Foreign Portfolio Investment as measured by Total Foreign Buying. The exchange rate does not have a significant effect on Foreign Portfolio Investment as measured by Total Foreign Buying.