Abstract. This research was conducted to examine the effect of disclosure of corporate social responsibility and institutional ownership on tax avoidance. In this study, disclosure of corporate social responsibility is measured by GRI-G4, institutional ownership is measured by comparing the number of institutional shares with the number of shares outstanding and tax avoidance measured by CETR. The research method used is descriptive verification method with a quantity approach and using multiple linear regression analysis test equipment. The data collection technique was carried out by using a population of 47 mining companies listing and listing the Indonesian Stock Exchange for 3 years in 2015-2017. So that a sample of 12 companies that met the criteria was obtained.The results of this study indicate that (1) Corporate social responsibility has an effect on tax avoidance (2) institutional ownership affects tax avoidance.Keywords: Corporate Social Responsibility, Institutional Ownership, Tax AvoidanceAbstrak. Penelitian ini dilakukan untuk menguji pengaruh pengungkapan corporate social responsibility dan kepemilikan institusional terhadap tax avoidance. Dalam penelitian ini, pengungkapan  corporate social responsibility diukur dengan GRI-G4, kepemilikan institusional diukur dengan membandingkan jumlah saham institusi dengan jumlah saham yang beredar dan tax avoidance diukur dengan CETR. Metode penelitian yang digunakan adalah metode deskriptif verifikatif dengan pendekatan kuantitiaf dan menggunakan alat uji analisis regresi linier berganda. Teknik pengumpulan data dilakukan dengan menggunakan populasi pada 47 perusahaan pertambangan yang listing dan Bursa Efek Indonesia selama 3 tahun pada tahun 2015-2017. Sehingga diperoleh sampel 12 perusahaan yang memenuhi kriteria.Hasil penelitian ini menunjukkan bahwa (1) pengungkapan corporate social responsibility berpengaruh terhadap tax avoidance (2) kepemilikan institusional berpengaruh terhadap tax avoidance.Kata Kunci : Corporate Social Responsibility, Kepemilikan Institusional, Tax Avoidance