Rapid advances in digital sensors, networks, storage, and computation along with their availability at low cost is leading to the creation of huge collections of data -- dubbed as Big Data. This data has the potential for enabling new insights that can change the way business, science, and governments deliver services to their consumers and can impact society as a whole. This has led to the emergence of the Big Data Computing paradigm focusing on sensing, collection, storage, management and analysis of data from variety of sources to enable new value and insights. To realize the full potential of Big Data Computing, we need to address several challenges and develop suitable conceptual and technological solutions for dealing them. These include life-cycle management of data, large-scale storage, flexible processing infrastructure, data modelling, scalable machine learning and data analysis algorithms, techniques for sampling and making trade-off between data processing time and accuracy, and dealing with privacy and ethical issues involved in data sensing, storage, processing, and actions. The International Symposium on Big Data Computing (BDC) 2015 -- held in conjunction with 8th IEEE/ACM International Conference on Utility and Cloud Computing (UCC) 2015, December 7-10, 2015, St. Raphael Resort, Limassol, Cyprus, aims at bringing together international researchers, developers, policy makers, and users and to provide an international forum to present leading research activities, technical solutions, and results on a broad range of topics related to Big Data Computing paradigms, platforms and their applications. The conference features keynotes, technical presentations, posters, and workshops.