The Gross Enrollment Rate (GER) is one of the indicators used to see the level of education participation in Indonesia. One of the main focuses of this research is the low Gross Enrollment Rate (GER) for high school education in Indonesia. This is very clearly seen when compared to the other two levels of education. This study aims to examine and analyze the factors that affect the GER for high school / equivalent education in Indonesia in 2015-2019. The method used in this research is the quantitative method. The type of data used is secondary data from the National Statistics Agency (BPS). While the analysis technique used is a panel data regression model that combines cross-section data and time-series data. Where the cross-section data used covers 34 provinces in Indonesia, while the time series data used are from 2015-2019. The analysis in this study was carried out using the help of Microsoft Excel 2010 and Eviews 10. The results of the study found that partially poverty, student-to-teacher ratios, and per capita GRDP affected GER, while the number of education units (schools) had no effect at all. Another case with simultaneous testing results in all variables influencing GER.