With the increase of big data applications in diverse application fields, big data computing and application service is becoming a very hot topic among academic researchers, industry practitioners, and government agencies. As more big data and application systems are gradually used in different application domains (such as business, healthcare, transportation, environment monitor and assessment, and smart city development), big data quality and quality assurance of big data application service systems become very important and critical. Based on recent reports, it has been estimated that erroneous data costs US businesses 600 billion dollars annually. This workshop will focus on the subject of quality assurance issues and challenges for big data and application service systems. There are emergent needs for research problems and directions on this subject in terms of quality control models, automation validation methods, approaches, and service platforms as well as TaaS (Testing-as-a-service) and other novel test automation techniques. We invite original papers from both academia and industry