In today's world, it is appallingly hard to run a global business, spread over multiple continents without adopting cloud computing technology. Cloud computing makes it easy, saves bucks, reduces IT burden, and helps organisations to focus on customer requirements, market strategy, growth, revenue, and profit, etc. While the organisations are busy planning, selecting, migrating their core business data and applications to the cloud, at the same time it is pertinent to evaluate the service quality of cloud service providers. This will help organisations to adopt the right cloud service provider as per their business requirements. Eleven cloud service quality factors have been explored through an extensive review of the literature and then interpretive structural modelling (ISM) has been used to find out the driving and dependent factors of the cloud service quality and contextual relations among them. This study reveals six driving factors of the cloud service quality namely availability, reliability, scalability, security, service responsiveness, and usability.