Much research about green product development and marketing has been proposed due to consumers' awareness of environmental protection and the international severe environmental regulations. Despite the scholarly attention paid to green issues, the market shares of many green products have not increased significantly in accordance with academic pursuit and interest over the past decade. A major reason for this lies in the fact that many green products in the marketplace cannot fulfill consumers' expectations because gaps exist between consumers' expectations and their perceptions of those products. This problem has been left unnoticed and even unexplored in previous research. As a result, this study purports to adopt the service quality model for drafting a model describing the gaps existing between consumers' expectations and their perceptions, and adopt the notion of SERVQUAL instrument to develop a green product instrument for measuring these gaps. This green product instrument is built upon the basic attributes of product quality, attributes for measuring environmental performance and eco-certification of green products. By means of the proposed instrument, we find that gaps do exist between customers' expectations and their perceptions related to green information products. The larger gaps existing between consumers' expectations and their perceptions of green information products are environmental attributes of green information products. Finally, suggestions are provided for the managerial use of the proposed instrument, and a number of future research issues are also identified.