The purpose of this research was to investigate the effect of accrual and real earning management on IPO underpricing which was measured by initial return, on the first day of trading in Indonesia Stock Exchange, of Indonesian manufacturing companies during 2010-2014. This research was conducted using purposive sampling technique from 20 analyzed manufacturing companies. Earnings management variable was measured using discretionary accruals, abnormal cash flow, abnormal production cost, and abnormal discretionary expenses while IPO underpricing was calculated using the initial return on the first day of stock trading in stock exchange. This research used ordinary least squares technique (OLS) multiple linear regression analysis. The result of this study revealed that the real earning management practice through abnormal cash flow had a positive effect on IPO underpricing while the other earnings management proxy had a negative significant effect on underpricing. This finding indicated that every earnings management practice could give an effect in a different direction on IPO underpricing phenomenon, as a response of investors on the published company's performance. Hence, this study's finding provided a significant empirical contribution to the signalling theory, in particularly for the issue of IPO underpricing in Indonesian Capital Market practices. ABSTRAK Penelitian ini bertujuan untuk melihat pengaruh manajemen laba akrual dan riil terhadap IPO underpricing yang diukur dengan initial return hari pertama perdagangan saham di bursa pada perusahaan-perusahaan manufaktur yang melakukan IPO di Bursa Efek Indonesia periode Tahun 2010-2014. Penelitian ini menggunakan teknik purposive sampling dengan total 20 perusahaan manufaktur yang dianalisis. Variabel manajemen laba diukur dengan menggunakan proksi discretionary accruals, abnormal cash flow, abnormal production cost, dan abnormal discretionary expenses. Sedangkan, variabel underpricing dihitung menggunakan initial return pada hari pertama perdagangan saham di bursa. Penelitian ini menggunakan teknik ordinary least squares (OLS) multiple linear regression analysis. Hasil dari penelitian ini menemukan bahwa praktik manajemen laba riil melalui abnormal cash flow berpengaruh positif signifikan terhadap adanya fenomena underpricing. Sementara, proksi manajemen laba lainnya berpengaruh negatif signifikan terhadap underpricing. Hal ini tentunya mengindikasikan bahwa setiap praktik manajemen laba dapat memberikan pengaruh dalam arah yang berbeda terhadap fenomena IPO underpricing, sebagai respons investor atas kinerja perusahaan yang dipublikasikan. Hal ini tentunya memberikan kontribusi empiris bagi teori sinyal pada praktek Pasar Modal Indonesia, khususnya dalam topik IPO underpricing.