The second edition of the IAA-CSIC Severo Ochoa School on Machine Learning, Big Data, and Deep Learning in Astronomy (SOMACHINE 2020) will be held at the Instituto de Astrofísica de Andalucía (CSIC), Granada, from Monday 19th to Friday 23rd of April 2021. It is directed at researchers in astrophysics of all levels and aims at providing them with a thorough background in the advanced data processing techniques of Machine Learning, Big Data, and Deep Learning. Classes will be taught by experts from the Andalusian Institute of Data Science and Computational Intelligence (DaSCI) of the University of Granada (UGR), that belongs to the worldwide leading research institutes in its field. The theoretical lessons will be complemented by practical hands-on lessons and lectures on applications of Machine Learning, Big Data, and Deep Learning in astrophysical research.