Abstrak. Penelitian ini bertujuan untuk mengetahui pengaruh umur perusahaan, ukuran perusahaan, return on equity (ROE), persentase saham yang ditawarkan, price earning ratio (PER), dan kondisi pasar terhadap underpricing. Populasi dalam penelitian ini adalah perusahaan yang melakukan initial public offering (IPO) di Bursa Efek Indonesia (BEI) pada tahun 2017-2019. Analisis data menggunakan metode regresi berganda dan pemilihan sampel dalam penelitian ini menggunakan metode purposive sampling dengan jumlah sampel sebanyak 103 perusahaan. Hasil penelitian menunjukkan bahwa umur perusahaan, ukuran perusahaan, return on equity (ROE), persentase saham yang ditawarkan, price earning ratio (PER), dan kondisi pasar memiliki hubungan yang rendah. Hasil uji hipotesis secara simultan menunjukkan bahwa umur perusahaan, ukuran perusahaan, return on equity (ROE), persentase saham yang ditawarkan, price earning ratio (PER), dan kondisi pasar berpengaruh secara simultan terhadap underpricing. Sedangkan hasil pengujian secara parsial diperoleh hasil bahwa ukuran perusahaan dan return on equity (ROE) berpengaruh terhadap underpricing, sedangkan variabel independen lainnya seperti umur perusahaan, persentase saham yang ditawarkan, price earning ratio (PER), dan kondisi pasar tidak berpengaruh terhadap underpricing. Kata Kunci: Umur Perusahaan, Ukuran Perusahaan, Return On Equity (ROE), Persentase Saham Yang Ditawarkan, Price Earning Ratio (PER), Dan Kondisi Pasar, Underpricing, Initial Public Offering (IPO).Abstract. This study aims to determine the effect of company age, firm size, return on equity (ROE), percentage of shares offered, price earning ratio (PER), and market conditions on underpricing. The population in this study are companies that conduct initial public offerings (IPO) on the Indonesia Stock Exchange (IDX) in 2017-2019. Data analysis using multiple regression method and sample selection in this study using purposive sampling method with a sample size of 103 companies. The results showed that company age, firm size, return on equity (ROE), percentage of shares offered, price earning ratio (PER), and market conditions had a low relationship. The simultaneous hypothesis test results show that company age, firm size, return on equity (ROE), percentage of shares offered, price earning ratio (PER), and market conditions simultaneously influence underpricing. While the partial test results show that company size and return on equity (ROE) have an effect on underpricing, while other independent variables such as company age, percentage of shares offered, price earning ratio (PER), and market conditions have no effect on underpricing.Keywords: Company Age, Company Size, Return On Equity (ROE), Percentage of Shares Offered, Price Earning Ratio (PER), And Market Conditions, Underpricing, Initial Public Offering (IPO).