In the Industry 4.0 era, numerous manufacturing enterprises have tried to obtain a smart manufacturing system. A key component of a smart manufacturing system is data analytics to support optimal decision-making in production systems. Consequently, many IT service providers have developed data analytics services. However, many small- and medium-sized enterprises (SMEs) have very low penetration of data analytics services compared to large enterprises because of the low profitability for IT service providers. Mass-customizable data analytics (McDA) services, which can be applied to various manufacturing SMEs, can give IT service providers the opportunity to increase their sales and thus their profits by applying services to more companies at little extra cost. This paper proposes a conceptual development process of McDA services for manufacturing SMEs and suggests future research issues. We believe that this paper can contribute to the dissemination of a smart manufacturing system.